2/n
I ran with #Alphafly3 today again. Before the run I checked the soles of the shoes: the right shoe (the left one in the pic) is clearly worn out more than the left, and the outside of the sole was worn out more than the inside.
This prompted me into doing two things in today's run: planting my left foot more firmly when landing, and shifting weight to the inside of the right foot when landing on it. No soreness!
I'll still need to root-cause this.