Using parking mode will drain the 12v battery. Apart from maybe plugging a battery charger one night per week to keep it topped up, the inly other option is to run the dashcams from a seperate powerbank and charge that up when requited.
Parking mode wiuld be good, but its a power drain you could do without.
Or just dont switch on parking mode? Realistically do you live in an area where you need that to happen?
I dont care, its not my car….lol.