Aug 19 2020
microsoft edge whether it is a full version or a beta, dev version will crash frequently in big sur system.
Aug 22 2020
Hi there, you are welcome to the Microsoft Edge Insider Community Hub!
According to @josh_bodner's Dev channel update post about your issue:
Mac users running the OS 11 preview (Big Sur) may have issues with all versions of Edge either crashing or not launching to begin with. We’ve identified the issue and are working to get it resolved before Big Sur is officially released.