matchboxbananasynergy I've done other tests so I'll try to summarize :
In the main profile, I downloaded QUIK, QKSMS and Fossify SMS Messenger in .apk via the Github repositories, none of them work, in Sandboxed google play in the private area, I downloaded Google Messages and Fossify SMS Messenger, the Google Messages download fails and Fossify SMS Messenger crashes on opening with an unexpected error.
In the second profile where I run Sandboxed google play in this same profile, I get the same scenario with the difference that Fossify SMS Messenger opens via Sandboxed google play, only I'm still get this message so I can't use it.
My goal here is not the SMS app, I don't care, I want to retry configuring the RCS with opportunistic E2EE via Google Messages and it needs to be used as the default SMS app, I want to use it in Private Space, so let's assume it works works in the main profile, it's not important to me as I don't intend to use it that way.
matchboxbananasynergy I was also able to disable the AOSP messaging app.
In Android 15 ?