The suffix is not important to me, but here's a few suggestions: _2v2, _2on2, _2x2 etc.

1.) Dust2
Everything is cut off, except from long, catwalk and middle. Bombsite B is moved near CT spawn, where the entrance to bombsite B would be the double doors in middle.
Alternatively, the double doors are closed, but the lower tunnels leads from T middle ("green box", at shortcut/suicide) to CT middle (B ramp/slope).

2.) Nuke
Ramp is closed up, but you can still go into the vents, however, the only passage still open from the vents is to backsteps. Bombsite B is moved into garage, but the gate facing towards T spawn is closed up.
A brick sticking out from the wall above the roof of main entrance to bombsite A, makes it able for you to jump up on the ventilator (the white box). This makes it able for only one terrorist to jump from the T roof to silo, from silo to main roof, and from ventilator to skywalk and potentially backstab any CT.

3.) Inferno
Banana is mirrored and rotated towards CT spawn, and bombsite B is moved to CT spawn and rotated towards banana.