Maybe it’s possible with the repair script from @martijnpoppen. But I’m not sure.
I assume it’s only possible if the devices use exactly the same capabilities in both apps.
Therefore, I recommend that you ask in the linked topic.
May I ask why you want to change the app?
“Official” doesn’t mean that the app is programmed by Sonoff itself. The “Official” Sonoff app is just called “Official” because the programmer pays a certain amount of money to Athom every year, I think it’s about €100. So it’s a bit like the blue tick on Twitter/X.
However, “Official” apps are also available for Homey Cloud, which isn’t the case with the community apps. I don’t know whether there are any other differences.
Btw, the “Official” Sonoff App supports 17 devices, the test version off the SONOFF Zigbee App supports 22 devices:
