Issues connecting to a mixed Waterfall Network from modded Client

Hi there,

I have the following Issue in the Enigmaica6 E6 Launcher.

I cannot join any Vanilla Server, One of these is the Rest of our Network which I wished to connect with the Enigmatica Server. All Servers are 1.16.5!

When Connecting I get the Following Message:
Internal Exception: java.lang.ClassCastException: net.minecraft.world.biome.Biome$Category cannot be cast to Java.lang.String

Does anyone have an Idea how to fix this?

Thanks in Advance,

Schnitzeltoast

I think Vanilla servers cant support bungeecord or waterfall you need paper or spigot server to support bungeecord or waterfall