Arsy said:
Copy-paste artist url (twitter or pixiv) to Source column in upload page and click "Find artist".
Example: https://www.pixiv.net/en/users/68864 or https://www.pixiv.net/users/68864 or https://www.pixiv.net/member.php?id=68864

Or you can use SauceNAO or IQDB.
Thanks, that help me a lot,But when I click "Find artist", it gives me more artist tags, I don't know which one is the artist tag in use,such as https://www.pixiv.net/en/users/68864
It gives me

49 (yonkyuu)
778-go
7fuji 06
94 (644534209)
abarerumidori
abii
aida (chinhung0612)
aida takanobu
ainili
ainy
aka tonbo (lovetow)
akatsuki akane
aling
alt
amano kusatsu
ame arare
an-telin
anarchojs
anbo
aosaki yukina