--sub-scale doesn't work any more on such kind of subtitles, any ideas?

[hooke007]

test.zip
Not sure which version started to fail.
mpv 0.37.0 works

[llyyr]

That still won't work because #14234 fixes a bug where sub-scale caused typesetting to also be affected by it. Your subtitle track uses \move tag so it gets detected as a sign.

#15512 for a potential fix, set that option to no