How to improve this

Bruno5234

Hi, I'm making a 2D game where I have a player moving always in the middle of the screen in the rigth direction, I want to give it the hability to split in two players where one is the mirror part of the other by pressing a button and then by releasing it the two players again form a single player , my problem is with this split.

What I made is make 2 players in the same place that can't collide with each other and by pressing "A" both players move away from the axis, releasing "A" causes the players to move to the axis. My problem is that I don't know how to make the players stay in the axis (because both continue moving after crossing the axis) and also how to make the player don't go out of the map (for the same reason).

I try to create colliders to block the movement of the players but the problem is that this colliders affect the movement of the player when it interact with other objects.

I hope I explained my problem