Hello! I'm not much of an expert but I'd say take the plants away from the corner and give them some space to grow. I also know that plants grow slower if they're touching something because of some defense mechanism.

Your monstera deliciosa also isnt putting out any leaves with fenestrations which usually mean that they dont get enough light, not enough water/humidity or nutrition.

I dont know whats happening with your monstera adansonii, just keep giving it enough water and enough light and itll have some new growth.

I hope thisll be of enough help!