try with:
https://github.com/rathena/rathena/blob/master/doc/script_commands.txt#L4531
*changebase <job ID number>{,<account ID>};
This command will change a character's appearance to that of the specified job
class. Nothing but appearance will change.
The command will run for the invoking character unless an account ID is given.
changebase Job_Novice; // Changes player to Novice sprite.
changebase Class; // Changes player back to default sprite.
https://github.com/rathena/rathena/blob/master/doc/script_commands.txt#L963
OnPCLoadMapEvent:
This special label triggers when a player steps in a map marked with the
'loadevent' mapflag and attaches its RID. The fact that this label requires a
mapflag for it to work is because, otherwise, it'd be server-wide and trigger
every time a player would change maps. Imagine the server load with 1,000 players
(oh the pain...)