Try This if Upload Gets Stuck at 100%

I tried multiple times to migrate a simple site using this plugin and then I remembered a similar issue that Duplicator also has when migrating sites.

If your upload completes at 100% but the install process cannot not proceed from there, try this.

Deactivate all plugins on the source site except for the AIOWPM plugin and re-export the site. Then try uploading this new file and see if you can proceed with the install once the file is fully uploaded.

It worked for me!