I personally don't know any gambit, I just try to play the opining following the basic principles. I saved this list from a comment in Reddit time ago:
Unavoidable 2nd move gambits:
- King's Gambit against 1.e4 e5.
- Smith-Morra against the Sicilian.
- Staunton Gambit against the Dutch.
- Blackmar-Diemer Gambit against 1.d4 d5.
- Tennison Gambit against the Scandinavian.
- Grob Gambit against 1.g4 d5.
Avoidable depending on the opponents follow-up but easy to get:
- Evans Gambit in the Italian.
- Traxler against the Knight Attack (Italian).
- Albin Countergambit against the Queen's Gambit.
- Stafford in the Petrov.