I can see that was must easier to achieve with Life360 since you could have an instance of the app running on each hub with a different place selected as 'home'. Trouble with this is your phone only reported to one server with Life360 and with OwnTracks it's the same but the server is your hub and as far as I can tell, there can only be one server the app will report to.
Quick idea would be to use rule machine to react to a different region being entered to control a virtual presence sensor for your 2nd home and expose that virtual sensor to the other hub via hub mesh.
EDIT: I linked this to [RELEASE] OwnTracks for Hubitat Presence Detection - #185 by zerosum74 so discussion could be continued there.
