All but one published (the NWSL site which has apparently stopped doing them) for week 21, and every site but one had the exact same rankings (the last just flipped the order on two teams)!
A reminder of what Power Rankings should be (not that every site does of course...):
”If two teams played tomorrow, given their current injury concerns, form, and other considerations, who is likely to win on a neutral field? All things being equal, who is the best team going forward, based on what we know now?”
As always, if you know of a site I have not used please let me know in the comments and I’ll look into adding it!