The idea that workplace writing needs to be more formal to be "professional" or "impressive" is a 19th-century zombie that just won't die.
When you get any kind of written communication from any business (including this very post from me), you're interested in one thing: THE CONTENT!
Either it's USEFUL to you or it's not (and you can hit DELETE).
If it's USEFUL, then either it’s CLEAR or not.
All you, as a reader, ask of workplace writing is that it be USEFUL and CLEAR. I doubt you’re giving bonus points for being adequately FORMAL…lol.
The key to workplace writing couldn't be any more simple:
Give readers USEFUL content and write CLEARLY.
Learn to trust writing in plain English—using the words you use when you talk to people at work—co-workers/clients/customers/other interested parties…all day long.
You can save the tuxedo for weddings.