YNAB pulls in most transactions programmatically if you connect accounts. Some accounts don’t sync (eg Apple) and other accounts will only do an initial sync (most 401ks and loan accounts). I think the sync restrictions are a factor of the accounts themselves and not YNAB; I’d love to know if I’m wrong there.
YNAB does not categorize things for you. It’s a different approach where you define money buckets, assign funds to the buckets, and categorize transactions into those buckets. I moved over when Mint got acquired because fuck Intuit and I haven’t really put a ton of time into trying to understand the different paradigm, so I’m not sure I’m explaining it properly. I didn’t use YNAB before because the paradigm isn’t how I’m used to thinking about my spend.
Don’t start the trial unless you’ve got time to think about setting up your buckets and spending targets. Or, if you just want to test the import because you’ll make time later to set it up, it’s probably worth the trial. There is a “family” plan that allows an account owner to share things; I think that’s worth it if you’ve got some people you share financial info with who also budget and you want to keep costs down.