The problem with that is that "会" is "can" in the context of a learned skill. So gramatically or rather, through definition, saying "Can you stay here?" Is incorrect. Using "能" or "可以" would be better words.

@RuhRoh1 is right. 会 does not mean “be allowed to (can)”. For more about 会 and 可以, see https://www.duolingo.com/comment/25702692