Can't connect with 1.9 to 1.9.2

[NPC-Master3304]

/viaversion dump Output

https://dump.viaversion.com/993e3c33bb3b716c58c173bf318a053778a8e3b336139beea50f6e76b6c12dc0

Console Error

No response

Bug Description

When you attempt to join any server on 1.21 with 1.9 to 1.9.2, you'll get disconnected.

Steps to Reproduce

1. Load up any version from 1.9 to 1.9.2
2. Join any 1.21 server.

Expected Behavior

To not get disconnected.

Additional Server Info

ViaProxy

Checklist

• [X] Via plugins are only running on EITHER the backend servers (e.g. Paper) OR the proxy (e.g. Velocity), not on both.
• [X] I have included a ViaVersion dump.
• [X] If applicable, I have included a paste (not a screenshot) of the error.
• [X] I have tried the latest build(s) from https://ci.viaversion.com/ and the issue still persists.
• [X] I have looked at https://www.spigotmc.org/resources/viarewind-legacy-support.52924/ and it does not offer a fix for my problem

[Barvalg]

[FlorianMichael]

Please provide the full log