Sponsorblock supports Invidious. Go into the Sponsorblock settings under Misc and enable it. You might have to add an instance’s URL (on the same settings page).

In your Invidious local settings, there should be a “Feed Menu” setting. This allows you to choose which tabs appear on your local homepage. (If you have an account, then these settings are for your account and should persistent anywhere you log in.) You should be able to choose “Popular” or “Trending” as one or more of your tabs.

For FreeTube, you can copy the link from your browser (from YouTube or any Invidious instances at least) and paste it into FreeTube’s search bar, and it will go directly to the desired video. If you use Firefox, Privacy Redirect has a setting (under Advanced Settings --> Invidious) to redirect all YouTube requests to FreeTube. You would have to turn the plugin off to search, then turn it on when you want to use it.

FreeTube currently has two sections “Most Popular” and “Trending” that fetch content from creators I haven’t subscribed to.

Hope this helps.