Brave has an entire contingent of the FOSS community up in arms. They claim that it is doing more data harvesting than Alphabet, and the EULA prevents anyone from finding out what they are doing with all that data scraping.
I don’t have a dog in the fight, other than as a windows user I would like to see FOSS adopted as quickly as possible since they have predicted all this shit for the last 30 years at least.
ETA: I know basically nothing about Vivaldi, though having used it, it seems to function as lightweight as chromium did back in the day. I have no comments on Edge.