Spigot 1.13.2 latest
LuckPerms 4.3.80
Namer 1.1.2

I am testing Namer, which forges the user name somewhere in the Mojang internals. The player UUID is unchanged, so I am still counted as Admin/OP, and LuckPerms still gives me full permissions appropriate to my real id and group. But

>perms user SlimeDog info
[18:40:55 INFO]: [LuckPerms] A user for SlimeDog could not be found.

Either use your real username or your UUID.

No worries. I posted only to ascertain if there was something that LP could do to recognize the situation. Obviously, I have the real playerName and UUID. And I would not allow players to use the Namer functionality in any event. :)