I'm going to say it's not happening. Arc System Works already has a lot on their plate with a new Guilty Gear and what seems to be a new Blazblue in the making as well. Cross Tag Battle seems to be retaining an audience too so they might continue making DLC for that as long as they can.
After the huge success of Dragon Ball Fighterz, I can see them making a sequel once next generation starts up. And Granblue also has a huge audience too, coupled with Cygames' bags of cash, will probably be going on for a while if there is positive reception and an active community for the game.
I feel like Persona 4 Arena Ultimax's community coming and going in such a short time period, mainly because of the long wait between the arcade and console releases, along with the fact that Guilty Gear Xrd came out only three months after the console release of Ultimax, and that Ultimax came out only on last generation hardware, made Arc System Works eventually move on from the series.
It really felt like something that they wanted to continue doing, and it was a great success at first, but now they have Dragon Ball to be their licensed fighter. And working with Namco Bandai, who are really invested into the Dragon Ball IP AND also have a great amount of eSports experience, is probably more beneficial to them as well.
And personally, I feel as though getting an Arena game now, after we have gotten Q2 and Dancing Star Night, with also The Royal and Scramble coming out soon, would be kind of awkward. I still think it's really annoying how every single 2014 Arc System Works fighter was ported to the PS4 and PC except for Ultimax, but I imagine at that point Atlus wanted to move on from Persona 4 and focus on Persona 5 marketing.
