I would advice against doing that, as there could be some bugs if you start follow people from different clients, which wipes your following list. But you can copy the npubs and search for them in your client.

At least, backup your list before you attempt such a thing.

And use https://chrome.google.com/webstore/detail/nos2x/kpgefcfmnafjgpblomihpgmejjdanjjp to sign in.