Unsure as to why players cannot join the server

Hello,

I am playing the Modified Cobblemon modpack and I am able to join the server, the server is also hosted on my pc, but yet no one else is able to join the server, they get an error code of fieldSize is too long yet I have triple checked to be sure that all of the mods are the same outside of the client side mods. The specific code is Internal Exception: io.netty.handler.codec.DecoderException: io.netty.handler.codec.EncoderException: Java.io.EOFException: fieldSize is too long! Length is 1638, but maximum is 38. The first number changes at random but it is always a fairly large number and I have tried looking and logs and it says that there are mismatched mods between the server and client yet they are both present so I am not sure what is creating an issue for players joining.
Client Log

https://pastebin.com/UxpcCXr6

https://pastebin.com/aWuHaN57

I had to split the client log because it was too large for a single pastebin, I have had all three friends try to join the server and they all get this message but the client logs provided are from the person joining from LAN. Forge version is 47.3.11. Any help or insight on what is causing the issue would be greatly appreciated.