Opening Repertoire for a "Positional" Player
You could play with White 1.Nf3 or 1.c4 and with Black 1.e4 e5 and after 1.d4 you play Nimzo and combine it with a Queens Gambit Declined or Ragozin. There are many possibilites of course. The Classical Slav or Queens Indian are also super solid openings.
Good luck

I am mostly a positional player myself, and I try to play everything to make my games more diverse. That said, the best luck I've had is with Caro, Owen and Pirc in response to 1. e4, Benoni and Slav in responce to 1. c4 and 1. d4, and something involving king-side fianchetto in response to 1. Nf3. For white, I feel most comfortable with 1. Nf3 or 1. c4, having a large flexibility to go into the type of positions I like, depending on the opponent's responses. I'm really happy when my opponent responds with 1. Nf3 d5, because Reti Opening is one of my favorite openings.

When I went through my super-positional stage around 1600 rating, I generally played 1.c4 as White, aiming for c4, Nf3, g3, Bg2, 0-0 and then react based on Black's set-up. Against 1.d4 I tried the Nimzo but had more success with the Benko Gambit; against 1.e4, I tried both the Scandinavian and Caro-Kann, but I had more success with the Kan Sicilian (though note that the English attack was not the popular choice it is now).
I learned quite a bit doing this, but note that it's possible to turn the sharpest variations into positional masterpieces, just as dull positions can become tactical minefields out of nowhere. It comes down to the player and the middlegame guiding plans, not the first moves of the game.

I like how people don't ever discuss the possibility of playing 1. e4 positionally. That's pretty much the goal of my white repertoire.

I like how people don't ever discuss the possibility of playing 1. e4 positionally. That's pretty much the goal of my white repertoire.
This old book https://www.amazon.com/Opening-Repertoire-Positional-Player-Eduard/dp/1857441524 also features 1. e4. Variations include the Alapin and the Short Variation.

Your opening choice doesn't make you a "positional player" as much as your moves and ideas. You can play positional chess in sharp, tactical lines - as long as you keep the tactics in check. That being said, I play Nimzo-Larsen (b3, Bb2 and Nf3 usually) as white, building on the queenside in most games and the Semi-Slav or a variation of the Modern as black. A lot of times I'll play the Kan Sicilian too

While positional understanding and tactics cannot be avoided completely, I would suggest the following in your case:
White: 1.e4
Against 1...e5 - Ruy Lopez. If 3...a6, take on c6 on move 4. The Berlin should be a non-issue for you. You will need to briefly brush up on other non-3...a6 lines.
Against 1...e6 - Advanced Variation. The center is blocked. It's all about understanding positional concepts like pawn levers, for example. Must be good at playing Good Knight vs Bad Bishop endings, you having the Knight.
Against 1...c5 - White gets zero advantage without playing the Open Sicilian, but against 2...d6 you can play the Prins (5.f3 instead of 5.Nc3) which avoids the wild Dragon, Najdorf, and Scheveningen with a positional Maroczy Bind structure. The same can be used against the Accelerated Dragon. Most 2...e6 Sicilians tend to be positional in nature. Against the Kalashnikov, play 6.c4 (the positional line), not 6.N1c3 (the tactical line)
Against 1...c6, the Advanced lines, Short Variation (4.Nf3, NOT 4.Nc3)
Black:
Against 1.e4: Caro-Kann, 1...e5 (particularly the Berlin - 3...Nf6 against the Ruy Lopez). You could also experiment with certain lines of the French, but I'd avoid the Winawer if you are looking to avoid tactics. The Rubinstein (3...dxe4 and 4...Nd7 against EITHER 3.Nd2 or 3.Nc3 might be right up your alley). Certain Sicilians might work too, particularly e6-Sicilians, like the Taimanov or Kan. AVOID 2...d6 Sicilians or wild lines like the Alekhine, Pirc, Modern, or Winawer French.
Against 1.d4: QGD, Slav. If you are ok with the Nimzo-Indian, maybe the King's Indian is worth a shot. It tends to be a positional defense, but you must be willing to sacrifice material. It's not sacrificing for mate with wild tactics. It's understanding when a Bishop or Knight is worth more than a Rook, or when a pawn that is critical to White's defense is worth a whole piece to remove. Avoid the Modern Benoni, Grunfeld, or Leningrad Dutch.
Hope this helps.

I like how people don't ever discuss the possibility of playing 1. e4 positionally. That's pretty much the goal of my white repertoire.
LOL - I put up Post #13 before reading this - read post #1 and responded.
So I guess there's a few of us out there! But yes, it is funny how most clowns seem to think that 1.e4 automatically means that White is out for a bloodbath!

I mean no offence, but there is no such thing as a "positional style" at 1300 elo.
So-called positional style is often claimed by beginners (it included myself) who have not yet developped the slightest tactical skill and rely on strategical rules of thumb that they more or less handle about pawn structure and so forth, leading them to think they are "positional" players.
Just stick to opening principles, do tactical exercices, improve your global level and only then bother yourself with openings repertoire, otherwise it will do nothing but slow you down.

You could play with White 1.Nf3 or 1.c4 and with Black 1.e4 e5 and after 1.d4 you play Nimzo and combine it with a Queens Gambit Declined or Ragozin. There are many possibilites of course. The Classical Slav or Queens Indian are also super solid openings.
Good luck
I use to be an e4 player, but didn't like most of blacks replies. I played this for around 10 years. I decided to get good at the sicilian as black. I now feel comfortable playing c4 as white and playing Nf3 occasionally. I feel c4 forces black to play some awkward games for their style. Nimzo players will still try Bb4 but not Nd5 repels the bishop. And b3 is a great move not and accepted instead of a refuted move in many e4 lines or just b3 by itself. The opening is flexible so you can play many different types of positions as well. I didn't like d4 because I didn't know the game plans for white and isolated pawn advantages and disadvantages. As I'm learning them I am less fearfull of playing d4 lines and pawn positions.

As white
, I usually plays e4 as first move, probably going for Italian Game or Spanish depending on what black's response. I also play d4 and go for the London system, London is a quiet opening that's why i love that opening I also go for queen's gambit if black would play d5 as a reply on my d4.
As black, I play the Alekhine's defense, Scandinavian Defense, French Defence(Classical Variation), e5, and Sicilian Defense(Najdorf and Dragon Variation) as an answer to e4. Against d4, I play the King's Indian Defense and Nimzo Indian Defense

When you say you are a "positional player", do you go for slow long maneuvering game or go for certain positions with some pawn formation e.g. Isolated pawn etc.. Or both?
My playing style could be described as "positional". I would call it quieter, as those are the kind of positions I enjoy/ are best at. If anyone has any ideas as to what I could play, please state them in the comments. Currently I play d4 only with white, either the Caro Kann or the Owens Defence against e4
and the nimzo/bogo indian as black in response to d4. But I would like to check if anyone has any other options. As I said, I prefer quiet positions with little tactics.