Note: I really mean female IMs and not WIMs
All IM version: List of records for youngest international masters since 1950?
WIM version: List of records for youngest WIMs (woman international masters) since 1950?
On Wiki, we have the List of youngest grandmasters since 1950. What about female IMs instead of GMs?
Edit 1: Who was/were even the 1st female international master/s?
Edit 2: I guess Judit Polgar is on this list because:
With these three results, she completed the requirements for the International Master title; at the time, she was the youngest player ever to have achieved this distinction.[45] Both Bobby Fischer and Garry Kasparov were 14 when they were awarded the title; Polgár was 12.[46] It was during this time that former World Champion Mikhail Tal said Polgár had the potential to win the men's World Championship.[47]