At my work we let people use whatever name they want for any IT stuff. Basically you give us one name and that'll be your email, Teams, account ID, basically anything your coworkers can see. The only time the legal name is used is on HR documents and payroll, but they're working to adjust that too, which would be super great. There's no reason anyone should have to be referred by as a name that they don't feel is their own or that triggers traumas.