VLC command line or other ways to convert .mp3 to .mp4 with an image file for uploading to Youtube

Question

I have 2 to 6 .mp3 files every day (I'm on Windows 10), and I need to convert them to .mp4 files with an image (same image every day for all files), those mp4 files are to be uploaded to YouTube. File names need to be the same (only the extension changes from .mp3 to .mp4)

I'm trying to create a .bat file to run every day which does everything for me.

Does anyone know if VLC can do this from the command line? If not, are there any other ways?

The best solution I've found so far is:

for %%a in (*.mp3) do "D:\VLC\vlc.exe" -I dummy "%%a" --sout=#transcode{vcodec="h264",fps="23.97",acodec="mpga",ab="128"}:std{access="file",mux=ts,dst="%%a.mp4"} vlc://quit

but it doesn't add an image and filename is incorrect, and the outputed mp4 is strange, it crashes when I jump in time.