This is probably the worst safespot to still be useful. A few things to note:

You have to be flush with the left wall in order for it to work; it's precise enough that where turning to face to the right without leaving the safespot is nigh-impossible.

If you push Gemini Man to phase 2 by hitting the one in the air, the Gemini Man on the ground will shoot a pellet immediately followed by a Gemini Laser. Since this is impossible to dodge, you need to prevent that from occurring by ending phase 1 with a shot that hits the Gemini Man on the ground.

Getting through the phase transition and phase 2 unscathed is still fairly tricky.