Weird hack to sorta sort by popularity on pixiv without a membership.

It sorts it by the number of stars (like likes)

Search for something like 10000users 入り or 5000users 入り and then the Japanese name of the show:

ユーリ!!! on ICE

Which you can find on MAL if you don’t know its best to go 10000users 入り ユーリ!!! on ICE, then 5000users 入り ユーリ!!! on ICE, then 1000users 入り ユーリ!!! on ICE, as you usually find the best stuff.