I’m not American, but I was taught English by someone with an American accent so!
I feel like Nivaan would be easier for an English-speaker, since people would pronounce Anvay as un-vei instead of un-vai
I agree with all that’s been said. I would say Ni-vaan and An-vey.
I think Ni-vaan might also sound good to American ears (but still unique and beautiful) because there are lots of two syllable boy names ending in -en, and I can see this fact making it easier for others to grasp.
Not exactly the same, but some similar rhythm…I’m can hear a teacher saying, “Nivaan, [name_u]Aiden[/name_u], [name_m]Ethan[/name_m], get back here!”
I would have guessed Nivaan as “niv-ahn” with the last syllable rhyming with the name [name_u]Shawn[/name_u].
I would have guessed Anvay as “ahn-vay” with the first syllable rhyming with the name [name_u]Shawn[/name_u].
So I think I’d have been closer with Nivaan. It seems a bit easier of the two for english speakers to say.