question about watch + strap together

hello.

i have a vivosmart 5. i know its not compatible with a chest strap. if i buy a chest strap (lets say the dual) and wear it simultaneously, am I right in understanding:

• that BOTH will upload data to garmin connect, and in my final activity report, the chest strap data will overwrite the wrist monitor data, where applicable (eg HR)

• i will have no way to see the chest strap HR during activity as it doesnt transmit to that particular fitness tracker

• the chest strap can transmit to a compatible cardio machine, meanwhile having nothing to do with the vivosmart (I dont see why not)

• the chest strap, although providing more accurate HR, does not contribute to calculation of HRV or stress score?

thanks in advance for your expertise!