I tried Stardew Checkup with one of my saves and it just said whether I had all Stardrops or not, not which ones I'd gotten yet. It seems that the more common missing Stardrops may be:
Master Angler (if you don't like fishing)
12.5
with spouse/roomie (if you don't play that side of the game)
Maybe Old Master Cannoli if you accidentally remove that quest from your Quest List
If you skip the Fair because Lewis is too judgemental, you'll miss that one
If you haven't finished the Museum yet because you forget there's such a remote part of the map, that's another
That just leaves Krobus' and the one at Level 100 in the Mines but you can't be very far in the game and miss those, I think?