Fedified.com is a list of Twitter-verified accounts that have moved to Mastodon. This is a hand-curated list, so it's updated a few times a day. https://fedified.com/
Fedified — Notable Twitter accounts on the Fediverse

Protecting public figures, journalists, creators, companies, and brands on the fediverse by verifying common ownership of Twitter Verified and Mastodon accounts

Mastodon 🤝 Twitter Verified ➡️ Fedified
@taylorlorenz when I try to click through from the mastodon handles to follow the people it doesn’t work and prompts me to migrate my account (?!) but if I just go back to the main Mastodon instance and search the names I can easily follow them. One solution: make this an exportable CSV file that I could then import and follow many of them with a couple of clicks. Any more detailed guidance as to how to use this list efficiently without having to click many times for each name?
@HelloAndrew That's a Mastodon thing, you can't easily one click follow unless you're on the same instance. Easiest method I've found is to copy their full username and server, then paste that into your search box on your own instance. It's clunky but it works.
@torgospizza that’s what I’ve been doing but it’s incredibly time consuming. I wish someone would make a CSV file out of this it would be so much easier to import that. In any case thanks for your reply!
It doesn’t help that my iPad is on low battery and if you’re plugged into power then typing on an iPad becomes almost impossible.
@torgospizza @HelloAndrew when I click Follow on a profile on another server I'm prompted to enter my username@server and it redirects me, have done this a couple times and it seems to work well but might depend on the server
@garethwilliams @torgospizza @HelloAndrew it's the general design, but it's really painfully tedious for most people which is why the ask if for CSV that one can use to mass import. (The idea that humans would want CSV is amazingly bizarre–as a developer adjacent person at a company that deals with CSV files.)
@HelloAndrew @taylorlorenz if these are all account you already follow on twitter, you can try a tool called debirdify: https://pruvisto.org/debirdify/ which allows you to automatically find available mastodon equivalents of accounts you follow on twitter and export them as a CSV. I hope this is helpful!
Debirdify

This is a web app that helps you find out which of the people you follow on Twitter are on Mastodon/in the Fediverse already and follow all of them easily.

@HelloAndrew @taylorlorenz It requires you to authorize it to access you twitter account, so be mindful of the possible security risks. Here’s a toot by the creator of debirdify, Manuel Eberl, introducing the tool: https://graz.social/@pruvisto/109257404426481007
Manuel Eberl (@[email protected])

Okay, I hacked something together that tries to figure out if the people you (or somebody else) follows on Twitter have Mastodon account. Here it is: https://pruvisto.org/debirdify/ Very experimental. Not sure if I will keep it online forever. I'll put it on Github as well some time soon I think.

graz.social