Hmm ... I'm not sure if either of these help, but I'll throw them out there anyway, just in case.

As a Linux user, I'd normally do something like that with the command line tool 'sox' (Sound eXchange), but I'm not sure if sox is available on Windows.
e.g.:
Code
sox --norm=-10 infile.flac outfile.flac

I've recently use MixBus to mix down some live sessions and realised that it has an 'analyse' option that will report if the output would been various audio standards, e.g., for YouTube, Spotify, Soundcloud, Deezer, CD, etc... That would, though, mean importing them, adjusting, analysing and exporting, which is much more work than I presume you want to do.

Hopefully a better answer will come along soon.

Jazz relative beginner, starting at a much older age than was helpful.
AVL:MXE Linux; Windows 11
BIAB2025 Audiophile, a bunch of other software.
Kawai MP6, Ui24R, Focusrite Saffire Pro40 and Scarletts
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