Yeah it's #1 by a wide margin.
I think USC is #2...they have at least 13 between Thompson, Cooper, Leslie and Monica Lamb. I don't believe anyone else from USC has won but I could be wrong.
Tennessee has 12 total from 9 players per this report:
LVFLs Candace Parker, Diamond DeShields and Tonya Edwards have won a 2021 WNBA title with the Chicago Sky.
utsports.com
LSU is up there too...from my count I have 10:
Seimone Augustus-4
Sylvia Fowles-2
Elaine Powell-3
Temeka Johnson-1
Rutgers with 7 championships per this page:
@description
scarletknights.com
ND I think has 7:
Dev Peters-2
Ruth Riley-2
Jewel Loyd-2
Coquese Washington-1
Stanford from my count has 7:
Sonia Henning-1
Nneka-1
Pohlen-1
Nicole Powell-1
Olympia Scott-Richardson-1
Brooke Smith-1
Wiggins-1
Maryland has 6 graduates, at least 8 including transfers:
Walker Kimbrough-1
Tianna Hawkins-1
Toliver-2
Langhorne-2
Natasha Cloud-1 (transfer)
Lexie Brown-1 (transfer)