noun
same face syndrome; stamp-like character art
Manga/anime slang for when an artist draws all characters with nearly identical faces, as if using a personal stamp. Often used critically or humorously.
あの漫画家は判子絵で有名だ。
That manga artist is famous for same face syndrome.
最近のアニメは判子絵が多くて、キャラの区別がつかない。
A lot of recent anime have same face syndrome, so I can't tell the characters apart.
判子 means a personal stamp or seal. 判子絵 extends this metaphorically to describe art where faces look stamped from the same mold.
Compound of 判子 (hanko, 'personal stamp') and 絵 (e, 'picture'). The term likens repetitive character faces to images produced by a single stamp.