Here are my predictions for these set rumors if the theme continues in 2020.
Orisa & Efi could additionally include Efi's workshop is Numbani. Doomfist has a likely to low chance of appearing as an antagonist.
Rio Battle could be based on Rio De Janeiro with a high chance of including Lucio, Symmetra and maybe Sanjay idk, but if it's Rialto it could be based on Retribution and include Blackwatch Gabriel Reyes (Reaper pre fall of Overwatch), Blackwatch McCree, Blackwatch Genji, Blackwatch Moira, Antonio and maybe some Talon henchmen (Trooper, Heavy, Assassin, Sniper).
Omnic Titan has a high chance of being based on Torbjorn's digital comic "Destroyer", so the most likely minifigures are Torbjorn and his Ironclad guild rival Sven. If LEGO is generous maybe they can add in Brigitte, idk.
Talon Jet, could be based on the jet from Widowmaker's short "Alive", in that case it would include Widowmaker, Tracer, maybe Mondatta, one of his guards and possibly a Talon pilot. But best case scenario would be that it isn't based on the Alive short and includes Reaper, Widowmaker, Doomfist, Sombra, Moira, Sigma and a Talon Pilot, another possible minifigure addition could be Maximillien. These minifigures I listed for the set are all possible.
These are basically my takes on these sets. You can expand upon my prediction.