Training status syncing between devices

I usually switch between Instinct 2X and Fenix 7X Pro for my training (Instinct 2X for swim and Fenix 7X Pro for run/bike). How have i to set primary training device? Traing status changes if I set one or other device:

Instinct 2X:

Fenix 7X Pro:

Why it doesn't sync between two watches?