When you setup Microsoft Authenticator, it defaults to a QR code that will be invalid to standard TOTP apps. However, that's because it assumes you want to use the push notification of the app. If you click a button like "key without notify", it will give you a different QR code which is fully standard and works with common apps like this.
Wow, that is a great tip! I have been avoiding setting up a TOTP with Microsoft for months because I didn't want to install their app and I didn't know you could click "without notifications" to get a standard code. Super annoying that they insist on texting me every freaking time I log into email or Teams. Now I can use Aegis, phew!