Geek Native has been compiling these lists. I've noted the top in each, but click through for the top 10s. I'm not sure of some of the categories -- Carbon 2185 is sci-fi, surely, and it has The Masterclass Codex as a Western RPG (it's a D&D supplement). And it doesn't include current editions of D&D or Pathfinder, as neither are sold on DTRPG.
- The best selling western RPGs of 2019 (Strange Adventures Volume One)
- The best selling superhero RPGs of 2019 (Tiny Supers)
- The best selling pulp RPGs of 2019 (Dragon-Blooded: What Fire Has Wrought)
- The best selling modern genre RPGs of 2019 (Shadowrun 6E)
- The best selling horror RPGs of 2019 (Eclipse Phase 2E)
- The best selling family RPGs of 2019 (Hero Kids – Fantasy Expansion – Hero Advancement Cards)
- The best selling anime and cartoon RPGs of 2019 (Carbon 2185)
- The best selling sci-fi RPGs of 2019 (Cyberpunk Red Jumpstart Kit)
- The other best selling fantasy RPGs of 2019 (Shadowrun 6E)