Sony is also not strong in Japanese RPG
Sony has the console with the biggest amount of Japanese RPG. And some of the top selling ones are even PS (at least timed console) exclusive. Can you list big selling Japanese RPG not available on PS other than Pokemon?
Areas Sony aren’t strong in and need expertise are rpgs, fps, and sports games
In RPGs they have Bloodborne, Demon's Souls, Horizon and basically all the 3P ones. For FPS they have Bungie, Firewalk (ex-Bungie) plus Deviation working for them and basically all the 3P ones. In sports they have MLB and Gran Turismo and all the 3P ones. With recent acquisitions and announced projects they'll improve in the FPS, MP and GaaS areas.
They could improve in these genres specially in the 1st party area, but aren't/won't weak there specially when also considering the 3P for the whole context. In addition to this, in sports they could grow making their soccer/basket/American Football game, but it's almost impossible to fight against the current leaders specially considering the licensse the other ones may have in exclusivity.
When after some years they will go back to make more latively big acquisitions, I think their priority will be mobile games in addition to very popular console+PC games in Asia. Because these are the areas where they can make the biggest growth after growing in FPS/MP/GaaS plus PC.
Fighting has been growing since the SFIV launch and now is becoming one of the top genres. Sony is the console maker in the best position for fighting games thanks to 3P, but they have no 1P fighting team other than Lasengle (Melty Blood: Type Lumina, not a big player in the genre) under Sony Music. So I think that after investing in mobile + big in Asia stuff, I think they will consider to get one or more big fighting team.
Capcom and Namco Bandai would be the most appealing ones specially when also considering eSpors but they are in a great finantial shape and may not want to sell. Outside eSports, MK is the biggest player, and WB may be open to sell MK+Netherealm. ARC had with Dragon Ball FighterZ the most successful game ever and Sony may be interested on similar anime adaptations, plus Guilty Gear at least at launch was bigger than ever, even if not in a major position inside the genre. They are a good and cheap option for Sony, but since they are also now better than ever may not want to sell.
Regarding other genres, there's also horror but I'd say isn't a top selling genre. I think Resident Evil may be only the big selling IP. So if acquiring Capcom they'd secure this genre, plus also would help in RPG with MH and Dragon's Dogma plus also getting DMC in hack & slash and obviously SF for fighting. But again, I don't see Capcom being open to sale, because it's a familiar company and every year they break their financial records.