PvP Problem on Different Client Versions

[magef1x]

/viaversion dump Output

https://dump.viaversion.com/0aaaf6b7425463255c5fce19a4719e8198e516047c8eff33cea8db5d48fd46f8

Console Error

Put the paste.gg link or text here.

Bug Description

I'm using Viabackwards and Viaversions with dev builds and 1.16.5 players have some pvp and chunk issues. I fixed the chunk issue manually but the PVP issue cannot be resolved. If a 1.16.5 player and 1.20.1 try to fight in PVP allowed worldguard, they can't fight.

Notes

1. If players try to duel on pvp-allowed regions. They can fight. (Duel plugin: https://www.spigotmc.org/resources/duels.20171/)
2. If I remove worldguard from server, the problem will be fixed so it should be a wg compatibility issue.
3. Another solution is downgrading viaversion. If u download the stable version on spigot, you won't get this issue.
4. Removed every single plugin and tested every combination and it's confirmed, the problem is viaversion's dev build.

Steps to Reproduce

1. Login with a 1.16.5 Client
2. Login with a 1.20.1 Client
3. Create worldguard region with pvp allowed flag
4. Try to PvP

Expected Behavior

Players should fight

Additional Server Info

Latest paper 1.20.1 build, protocollib, worldguard and worldedit.

Checklist

• [X] Via plugins are only running on EITHER the backend servers (e.g. Paper) OR the proxy (e.g. BungeeCord), 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.

[Barvalg]

[Barvalg]

[magef1x]

Changed pvp arena location on stable viaversion and got this issue again :/ I don't have any idea how can I fix it rn

[Kichura]

This sounds more like a third-party plugin overriding all the pvp mechanics instead of us, please check if this problem is reproducable with just viaversion, viabackwards, worldedit and worldguard and not with anything else.