Answered
How do I turn off (or at least turn down) the snapshot sound effect in AFX?

It's very loud!

It's very loud!
I think you can replace it. Go to X:\Program Files\Adobe\Adobe After Effects 2022\Support Files\sounds (with X being your own drive letter) and replace snap.wav with e.g. a quieter version of it. The name and extension must be the same.
Already have an account? Login
Enter your E-mail address. We'll send you an e-mail with instructions to reset your password.