Isaac REPENTANCE multiplayer problems with mods. (The Binding of Isaac)

In Repentance, it's no secret that there is multiplayer. So, when the mods were added, my friend and I thought the mods would work fine, well, so, if you turn on the mod for the character, then only the host can play for the mod character. Who knows how to decide? After all, I also want to play for the characters, and when I host it lags.