I made a basic crossfade loop feature in this tool, which copies a section of the audio before the loop point; applies a fade in, and then mixes it with the same size portion at the end of the loop which has been faded out.
Send me a PM if you want to discuss it in more detail and i’ll be happy to help. The fades applied in my version are linear which don’t always give the best result because the volume can dip where the crossfade happens, if the fades are curved I think it will sound better… Hope that helps