export drupal2drupal migrate settings
There is a feature request for the Migrate module: Export migration configuration as code. Beware that this is highly experimental! Here is the summary of the issue:


Apply this patch to the Migrate module and be sure to clear cache. This patch makes your configuration exportable as a Feature.
You can now create a new Feature on the source site and select your configuration inside the Migrate fieldgroup. Check all options that apply and download/export your Feature.
Copy the Feature to your target site, enable it and then revert it to copy all your settings.