DC didn’t title them “What If?” only Marvel did that - I think up to 3 volumes now....yep 3 volumes and a couple one shots.
DC always called them imaginary stories as I remember.
YOURE good
I do recall the comics by Marvel with the big WHAT IF titles
Do you remember a comic or short story about a giant robot or alien that lived forever? circa 1966-67
thats all I recall, Ive wanted to find that comic for a long time