Everything gaming related to Sony Xperia has been related to PlayStation since 2010. I doubt they are going to change that now. Especially since they now seem to be consolidating their divisions more to be more effective.
Are you talking about the one time they partnered up to release a phone (back when they were Ericsson) or something else besides Xperia Play?
I remember that Sony Electronics and Sony Interactive Entertainment put Remote Play apps on Sony Tabs, and they did that PlayStation Certification program going where you could get PS1 games on a Sony device (I assume that's canceled? both of those programs date back to 2011, around the same time as Xperia Play,) and AFAIK they never brought PlayStation Now to Sony devices (or mobile in general; they did put it on Bravia Smart TVs) but they did intend to at some point. Otherwise I'm not coming up with too many other partnerships PlayStation and Sony Electronics has made on the mobile front. (SIE just made a partnership for an official PlayStation-licensed mobile gaming accessory, and
it wasn't though Sony Electronics.) They're separate groups in the Sony conglomeration, and I can think of more recent Sony
Music partnerships with PlayStation than I can Sony Electronics, particularly Sony Mobile.
The
Xperia gaming campaign has mostly been about streaming and Esports. (They signed up PUBG Mobile to use Sony phones as the "Official Smartphone Partner of PUBG Esports Global Tournaments 2022".) Looking at their announcement wording as well as the teaser clip point to more of that being the focus of this event. It looks to maybe be a phone with triggers (which is becoming common in gamer-oriented cellphones) and maybe an improvement on its streaming/recording/editing features.
So, I mean, I guess it's possible that the Sony Xperia event might have some PlayStation integration (this new phone doesn't appear to have buttons so I doubt it'd be a "PlayStation Edition" device, but it might still happen,) but I personally would not recommend staying up for this Japanese Xperia stream if you only care about PlayStation and not Sony phones...