There's still their external division. I wouldn't be surprised to see some sort of JRPG in collaboration with someone else.
External division such as senior producer Kentaro Motomura who was assistant producer on Wild Arms since WA3. His contact with MediaVision is still strong and like Scott Rohde said to Colin Moriarty at PSX 2015: "We will never retire an IP". He is now head of internal development of PlayStation WWS. On PS4 he was president of SCEA WWS and Shu was president of WWS. That means Scott Rohde is now controlling all studios and not just in US region.
MediaVision was looking for new character artists in July 2018 who can properly draw models of people (humans). It said for a PlayStation RPG. Their company had 156 people since April last year.
With the news of Silent Hill reboot and Silent Hills the new heads of WWS like Hermen Hulst, Scott Rohde and Asad Qizilbash is looking into strong IPs in their portfolio. Established IPs that can become bigger with right funds and support.
Something Hiphopgamer talked about in January. They want to diversify their portfolio with strong brands. Both creating new IPs into strong brands and grow established IPs. It's a new leadership under WWS who has different ideas in comparison to Shu, Allan Becker, etc.
Allan Becker has retired from WWS, btw. Shu becomes head of indies. Their direction for WWS and JAPAN Studio was not working. Either game development get stuck for years or the games have way too small peanut budgets with irrelevancy for public.
That's why that rumor about SCE was in talks with Universal Entertainment Corporation (Aruze Corp) to get something done with Koudelka/Shadow Hearts. The creator himself announce his studio last year, WILDROSE. Ohsawa is suspiciously to be working there (art director of Shadow Hearts). Plus the creator said WILDROSE is fully independent like MediaVision. Collaboration with Japan Studio's external division is not far-fetched.
If Sony can get license rights to SH they will shop around for more license rights because gamers care about these franchises.
Japan Studio as internal workforce did studio's producer hinted at towards the end of 2016:
"While I can't give any details yet, we're also moving forward with creation of ambitious new titles and new title concepts at the same time, so please continue to support SIE Japan Studio in 2017."
Their direction newly changed behind the scenes to prepare for next gen. Their old direction according to Gavin Moore at GDC 2014 was to make games with small teams. Their mantra from Allan Becker's direction was to make games you would normally not get on a console. This authority didn't work out in the end.
Now you can see on Gavin Moore's LinkedIn page that Japan Studio's current direction is to operate large teams. New leadership, new direction. That should also apply to external division. They are only going to make necessary games from now on. More Bloodborne, Wild Arms, less The Tomorrow Children, Rain stuff.