I have a Poké Gift that is claimable by each player once. It contains an Eevee.
This has existed since 8.2.0 so I'm not sure if it has already been changed.

If someone obtains multiple of these gifted Eevees, such as from a trade, only one of them can be used at a time.

Sending out one of them marks the others in the team with the green background as if they are out, but they are not.
https://i.imgur.com/ESJnYDh.png

When used in battle, you cannot switch between them.

They must have the same internal ID number or something.
This seems like a big oversight for the Poké Gift.

Hello,

Thank you for reporting this. I was able to reproduce what you are saying here. It seems as though any pokemon able to be claimed once by all players from a pokegift is not able to be throw out or used by multiple players at once. If multiple are obtained by 1 person, only 1 may be throw out or used in battle. If 2 players are online at the same time with the pokemon claimed from the pokeloot, only 1 person can throw out said pokemon. It will show up "green" (like it is out of pokeball) for the other player.

I will mark this to be moved to our internal tracker to be fixed. Thank you again for reporting this!

Moved to internal.

Fixed in Pixelmon Reforged 8.3.5

I still have this issue in 8.3.5

This is still not fixed in 8.3.8
I was going to submit a new bug report but it's exactly the same.

The gifts just need to generate random UUIDs for each mon. I made myself a command to randomize the UUID of a Pokemon, that fixes it.