Finsweet's chrome extension adds a nice import button here that allows you to bulk import your 301 redirects from CSV.
It offers a ton of additional features as well;
IMPORTANT: In the second half of 2023, Webflow released a new dashboard design which may break the export solutions we have here.
Adapting this technique, we can bulk export as well.
Jun-2023: Sam Pilgrim posted that some UI changes have broken the scripts above, and offers an alternative script.