There are charinfo and charsave directories (in "var" of d2dbs service) which contain files with the same names.
charinfo file is a cover, it used on character selection screen and portrait in chat room. It updates automatically from the charsave file. But it has several extra options like "dead", "ladder", "expansion" flags, and you will not able to play with the character if flags are not appropriate to a game mode. It can be modified using this tool https://api.pvpgn.pro/example/d2edit/
charsave file is default character format, which can be opened with HeroEditor. Just rename it to *.d2s to edit.
Note that a character should be offline before editing because it overwrites by a server after game end.
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