There are a few websites which list the correspondence between subreddits and communities:

1. https://sub.rehab/?visibleServices=lemmy
2. https://www.quippd.com/writing/2023/06/15/unofficial-subreddit-migration-list-lemmy-kbin-etc.html
3. https://redditmigration.com/

Is it possible/planned to have a tool which would automatically subscribe you to communities which match your subscribed subreddits? Perhaps subscribing to the most popular when there are multiple? This would make transitioning easier and more attractive.