Sonarr with nzb360 to manage it. Completely hands-free, couldn’t be easier to use once it’s set up.
If you don’t have your own hosting, search for “seedbox” hosting - there are plenty of great, relatively cheap options. I picked a hosting option which had the above apps already set up and ready to go, which made the whole thing seamless.
There are some good ones out there, just look for reviews. I haven’t had any issues with transcoding with the provider I use on a $5/mo plan.