I tried it and here's what you have to do in more detail:
Copy (e.g. from Steam version):
...\Microsoft Flight Simulator\Packages\Official\Steam\asobo-aircraft-e330\SimObjects\Airplanes\Asobo_E330\sound\Asobo_E330.PC.PCK
To (e.g. MS Store version):
...\Microsoft.Limitless_8wekyb3d8bbwe\LocalCache\Packages\Community\bksq-aircraft-velocityxl\SimObjects\Airplanes\Asobo_E330\Sound
Get MSFSLayoutGenerator
https://github.com/HughesMDflyer4/MSFSLayoutGenerator
Extract MSFSLayoutGenerator.exe anywhere, and drag and drop this file on top of the extracted MSFSLayoutGenerator.exe:
...\Microsoft.Limitless_8wekyb3d8bbwe\LocalCache\Packages\Community\bksq-aircraft-velocityxl\layout.json
Now the Velocity XL should have sound in MSFS 2024