GP
To import your Twitter follows and followers to a Mastodon account, go to https://fedifinder.glitch.me click Authorize to Extract Handles, scroll to the bottom of the page and export the CSV file, click on import/export and choose import on your Mastodon page, then merge CSV file.
Fedifinder

Fediverse accounts of your X/Twitter followings

Nov 20, 2022 at 5:49pmWeb
Show threadNathan SimmonsNov 20, 2022
@GPS_TX THIS IS SO HELPFUL!!!! Thank you!!
Show threadNathan SimmonsNov 20, 2022
@GPS_TX And it turns out to run **very** quickly! WOOT!