You should follow Twitch’s help article on follow bots Twitch Help Portal which instructs you to do nothing, as Twitch will ban the bots (and has been doing).
Using 3rd party tools like that provided by CommanderRoot can actually be harmful to your channel as it’s possible to either misuse the tool and block all followers, or even if you limit it to just his ‘bot list’ you’ll still block legitimate users as his bot list has proven to contain false-positives.
So to answer your question,
Twitch expects you to follow the help article on the matter and not block them at all, as Twitch will appropriately deal with the bots themselves without the same risk of tools by people like Root which have a harmful impact on your own channel.
Using the API to block users would take days because while you’re attempting to use it in a way that is allowed, it’s not a way in which it was designed for.