Minecraft Pi seems to assign a generic username StevePi123 (or other number). Can the username be changed?
Well…anything can be done, just depends on how much work you want to do (grin)
Here is a link you can follow that shows a way to do it, no guarantees you won’t mess up your system, so backup the SD card before you try https://www.raspberrypi.org/forums/viewtopic.php?f=66&t=186229&p=1176077&hilit=minecraft+stevepi+name#p1176077
Note:I have NOT tried this myself but I might give it a go tomorrow if I have some time.
So I gave it a try and it seems to have worked.
Might I ask why you want to change the name?