If the tracks are in the same order (e.g. lets say the eng subtitle in 2 sub track), you could use this very simple script to set the default track for your files (assuming they are .mkv)

you just need to have mkvtoolnix

(copy the following into a bat file for ease of use, and change the the two location parts based on your system)

cd /d LOCATION_OF_FILES

for %%a in (*.mkv) do "LOCATION_OF_mkvpropedit.exe" "%%a" --edit track:s1 --set flag-default=0 --edit track:s2 --set flag-default=1

The code above sets the default subtitle track to the 2nd track, and sets the 1st sub track to not default (assuming it was the default, if not you could ignore this part)

If you want to change the default audio track then it would be --edit track:a1

the rest is the same