For movies letterboxd does this quite nicely but it's a small part of the service rather than central. But any movie has a 'where to watch' section with links t

For movies letterboxd does this quite nicely but it's a small part of the service rather than central. But any movie has a 'where to watch' section with links to the movies on berries platforms, if you're subscribed of course. This is powered by a third party service, JustWatch, which might work for you - they do seem to have their own thing, not just an API