My killer Joe can't do any damage to creatures because Authme treats killer Joe as a player but he's not logged in
I found a way to do this, the configuration file for Authme;
unrestrictions:
# Below you can list all account names that AuthMe will ignore
# for registration or login. Configure it at your own risk!!
# This option adds compatibility with BuildCraft and some other mods.
# It is case-insensitive! Example:
UnrestrictedName:
- 'npcPlayer'

This method works, but I don't know which player ID is the killer Joe，Help Me :(

As quoted before, the name is [Killer Joe], see: https://github.com/SleepyTrousers/EnderIO/blob/master/enderio-machines/src/main/java/crazypants/enderio/machines/machine/killera/Attackera.java#L26-L27

However, any permission plugin/mod used in a Forge environment needs to understand Forge's FakePlayer API. There are just too many fake players around in plenty of mods (Ender IO alone has 5).

Also, we do NOT support using Ender IO on a server in 'offline' mode outside a development environment. Closed and locked.

Why don't you instead try to tell the devs of AuthMe not to treat fake players as players who aren't logged in, or perhaps not use plugins in a Forge environment when they weren't meant to.

why do you use authme specifically? (to be more specific, to my knowledge it's a replacement for saving player names on offline servers)

Because it's not a plugin error, it's just that I don't know the correct name, and I've tried these but they're not correct
UnrestrictedName:
- 'tile_killer_joe'
- 'tilekillerjoe'
- 'killer_joe'
- 'killerjoe'

try 'KillerJoe'

scratch that, only used for a chat message :D

private static final GameProfile DUMMY_PROFILE = new GameProfile(uuid, "[Killer Joe]");

try "[Killer Joe]"

for anything else use github search on the repo for "FakePlayerEIO", there is alawys a uuid and name for the specific fake player

It doesn't work.

i edited my comment a bit, if that does also not work, i point at my earlier question

It's eio_killera or something like

@tyler489 how is this defined? and with what did i come up then?

is that the forge fake player?!

Thank you for your help
I still haven't found the right way, but maybe I should try changing the plugin