I currently using two profile, one for personal another for work. I always using personal profile when using Edge only enter work profile for work related stuff. So I kind of expect Edge will start in personal profile when I start Edge but if I the profile I closed last is work then Edge will start in work profile.
Currently I think so far there is no way for setting which profile to open when first start Edge. Edge I think by default will startup in the last profile you closed.
So if there is no workaround for setting which profile to start then I hoped that devs implement a feature to allow us to set which profile to start everytime if there are multiple account.