pol2095 Next ARM processor only support 64 bit architecture.
I doubt this. The arm 64 architecture supports ARM 32 binaries, and I can’t see any reason they would remove it. You can still ship 32 bit apps now, and will be able to for a couple of months (longer if they are Unity apps).
Users expect these apps, as well as others shipped in recent months and years, to keep working on any new device they buy. So no-one is going to ship a device with 64-bit architecture only, at least not for a few years.
Google are doing what Apple did in 2015, requiring 64-bit for performance reasons. Apple disabled 32 bit apps altogether in iOS 11 two years later, but it will take Google much longer as the the installed base of older OS versions and cheaper 32-bit devices is much larger for Android.
As for Adobe and AIR, it should be straightforward as its something they’ve already done for iOS, macOS + Windows (both Flash Player and AIR), transitioned from 32 bit to 64 bit. It normally just means changing your build settings to also output 64 bit, then fixing any problems that arise due to e.g. coding assumptions about the architecture.