This. I don’t mind aliens speaking basic, but almost all of them do and with mostly with American accents, and this is what gives it a cosplah feel because they don’t sound alien at all.
StarkillerAG’s comments hit the nail on the head. The Mandalorian and the wider Mandoverse feels like cosplay Star Wars.
Also, let’s have aliens speaking alien languages.
If aliens are given foreign accents then everyone will accuse Disney of racism. I still remember when some criticized the accents of Jar Jar Binks and Nute Gunray.