I will give infuse a go and see how it is

Discord is the best place for help for actual budget, it is very active

Memmy is now in the App Store but you’re probably better off signing up through test flight so you can get the almost daily updates.

Yup, HomeKit can 100% work without internet. It’s a requirement of being HomeKit certified. I block internet access to all my HomeKit devices and they work just fine.