The mod doesnt support co-op at all, remote play or not, and due to the way the character functions...I cant really think of a way to make it work even.

thats really sad

imagine someone is isaac and has to survive and the other one is car but if isaac dies car does too

The issue is when the player thats not the car leaves the room. Getting tossed into another room with the car when you didnt go there can REALLY ♥♥♥♥ you up.

well you can just put the other car in the middle every time the other player goes into a room

Putting the car in the middle is also horrid, you have a lot less time to react depending on the situation....there are cases where Im currently doing it but I want to fix that when I have the time.
Still, adding co-op is not completley out of the question, but there are a lot of things to solve. Not to mention, if I add co-op support, people will also want to be able to play as 2 cars and the mod, being a mod that was rushed as a joke for April 1st, is definitely not designed for that rn.