I recently started playing with Edge and after adjusting the settings that I wanted I made a second profile for other web habits and I noticed that the secure DNS that I entered in the first profile is also in the second. After changing the DNS in the second profile I returned to the first only to found out that the change has passed and to the first profile. In Firefox every profile can be set with a differenet DNS setting. In the Edge is this not possible?
My thoughts would be... use Firefox, use something like Nirsoft QuickSetDNS to switch DNS servers, or look into some kind of virtualization. I'm not sure if a sandbox would allow different DNS, but you could certainly create a Virtual Machine. If OS licensing is an issue apparently there is a version of Edge for Linux. Maybe not the answer you wanted but that may not be an option.
edge has not fully separated profiles /edge/userdata/ a lot of common settings /edge/userdata/default/ profile1 /edge/userdata/profile1/ profile 2 its not like firefox. alternative to nirsoft https://www.netsetman.com/en/freeware (english) https://www.netsetman.com/de/freeware (german) my dns are set in my router, one default from provider and a backup to google or cf. for anything else i have an vpn extension installed.