Instead of transferring everything, export the CSV, open it in Excel, and sort by channel name. Remove the dead channels, the ones that haven't uploaded in a year, and the topics you no longer like. Then import the cleaned-up list (usually 20-30 channels) manually without any extensions.
If the built-in feature doesn't work for you, or you prefer a more manual approach, you can use an OPML (Outline Processor Markup Language) file to transfer your subscriptions. Here's how:
YouTube allows you to transfer your subscriptions to a new account, but there's a catch. This feature only works if you're transferring subscriptions from a Google account that's not verified or a YouTube account that's not linked to a Google account. If you're using a verified Google account or a YouTube account linked to a Google account, this method won't work for you. Instead of transferring everything, export the CSV, open
The tools are designed to be safe. They check for pre-existing subscriptions and will skip any channels you are already subscribed to on the new account. This prevents duplicates and avoids sending unnecessary API requests.
: Add the extension to your browser from the Chrome Web Store or Microsoft Edge Add-ons . If the built-in feature doesn't work for you,
: Log in to your old account on YouTube. Click the extension icon and select "Collect channel" while on your subscriptions feed .
While the automated and manual methods successfully copy your subscription list, keep in mind that certain data be transferred between separate Google accounts: If you're using a verified Google account or
YouTube does not support direct, automated subscription transfers between separate Google accounts .
SubShift: Transfer your YouTube subscriptions - Chrome Web Store
Note: Always be cautious when giving third-party apps access to your Google account permissions. Don't Forget Your Playlists