I have been having this issue in which whenever I save a replay, the player's names are completly randomized in a way that should make no sense at all.

For example, I recently won a match against Mytsterydedge in which I saved the replay, however, whenever I go look at the replay, it not only shows me in his place getting beat up, but instead of being him on the other side delievering the beating as it would be in case the roles were reversed, it's a completly different player by the user name of Japa13.

How can I fix this?

Same here. Often it works okay, but sometimes players are named wrong in the replay.

Also whenever I join a room, the names of current players in the corners of the screen very often don't match the names in the queue, idk if it's related

Maybe its a file corruption thing, but I have no idea about it, I looked up and so far no one else has related this same bugs.