@feditips Something like that; what saved me was that I had an earlier (not completely up to date, but recent enough to serve as a starting point) saved list of the hashtags I was following, which I was able to import. I didn't find any specialized import feature for that so I ended up using "toot tags_follow" for each tag. Either way, it should be copied before starting the account migration process.
Ironically, I even list hashtags myself in https://michael.kjorling.se/blog/2023/back-up-your-mastodon/.