Using iPhone/Apple Watch in a Google/Android environment with data sync

I guess I am just curious and want something new to play with. Most folks here probably understand…

Background:
In the mix are HA, Google Home Hub, Echo, Z-Wave devices, other integrations, iPhone and Android phone. I carry both phones. I also have a Pixel Watch 2 and a Galaxy Watch 6 (depending on my mood lol). No Homekit hub, but There are HK devices in the HK device integration.

I can use either the PW2 or GW6 to control my devices, scenes via Google Assistant voice commands (exposed via Nabu Casa). It works fine. The WearOS also allows me to sync calendars, get Google Voice messages, run apps, and tracks health metrics. I’ve also set up my watch to switch my Android phone between normal and Do Not Disturbe mode. My Android phone then sends a SMS to my iPhone, which triggers a shortcut to switch to DND as well. Same thing when I switch back to ring mode. One tap on my watch does it all.

Why am I wanting to use an Apple Watch? The only reason I can think of is because I just want something new to tinker with and see if I can make things work, so please help me with my madness.

Requirements with the Apple Watch, my research shows:

  1. Use voice to control my devices - has to be Siri, have to create shortcuts to get Siri to trigger. Is this true? Is there a better way?

  2. Use Apple Watch to also trigger DND on Android. Use the companion app sensor, which reports to HA, then I can get HA to control DND on Android. Is this correct and possible?

  3. Health metrics. I installed Google Fit and enabled Health Connect. Samsung Fit (from the Galaxy Watch) syncs via Health Connect. I then install Google Fit on iPhone and allow Google Fit to sync with Apple Health. This way, Google Fit becomes the hub of my health metrics. What do you think?

  4. Check my Google Calendar, get notifications for Google Voice and reply to messages (using voice as an option - Siri?).

Please let me know what you think and if the above research is correct and will work as I layed out. I would really appreciate your input or ideas. I want to be able to switch back and forth between WearOS and Apple Watch and maintain my health metrics and keep all the functions that I use as described.

Cheers.