Essential hosted worlds crashing whenever a player dies

[cntoo]

The bug consist in whenever a player die dont matter the form or the player when they click the respawn button the game goes with the message Internal Exception: io.netty.handler.codec.EncoderException: Failed to encode packet ‘clientbound/minecraft:custom_payload’

To Reproduce

1. Just any player dies on lan hosted servers
2. Click on Respawn button
3. Then the server closes no crash at all just server closed

Version: [6.0.0-alpha-f]
Mods added: Xaero's Minimap and Essential Mod
Mods removed: e4mc

Obs: I tried to install Packet Fixer but didnt fix it