Yes, there are tools that can fulfill what you are asking for. First, have a look at
FileBot.
It has a a CLI (and a GUI), it's scriptable, and it has many useful
options for renaming and sorting. You can use these options to group your HD and SD videos. It can even do movie sets and genres, so you can group your Spider-Man titles, or your comedies, or whatever. To identify episodes and give them Kodi-friendly names, it can look them up on
TheMovieDB,
TheTVDB,
AniDB, or
TVRage. It can download artwork and subtitles. It's a Java app that's packaged for several platforms.
There are two other cross-platform (Java) apps I use for library management:
tinyMediaManager and
MediaElch. They don't have the CLI power and easy renaming of FileBot, but they have more scrapers, and they're designed for browsing and managing collections, not just post-processing them. I like them for creating NFO files and fetching artwork, which greatly increases the speed and accuracy of scanning content into a new Kodi library. (And, of course, you don't have to re-download all that art every time.)
The first program is
tinyMediaManager. With this you can scrape your film and TV collection, either interactively or unattended. When your collection changes, you run an update. Once you set your directories and import your library, you can use this tool to manage your collection: change artwork, scrape new additions, edit the data from NFO files, and so on. I think you'll appreciate how it displays the artwork for each title as you browse your collection.
Then there's
MediaElch. Although MediaElch has many of the scraping capabilities of tinyMediaManager, their UIs are quite different, and both apps have distinctive features. For example, MediaElch can put all of your movie files into subfolders with one click. MediaElch also has a music scraper that allows you to fetch art and generate NFO files for artists; it can collect folksonomy tags as well. In practice, however, it doesn't fetch very much data, and there are many gaps. It uses the Universal Music Scraper, which can scrape
AllMusic,
Discogs, and
The Audio DB. Every album I tested also had MusicBrainz tags. But even with all these resources, the scraper returned very little content. It appears to get artwork only from The Audio DB. Even with these weaknesses, it can still be useful if you want to frontload artist data before importing your music collection into Kodi.
To its credit, MediaElch didn't modify my audio tags at all, even when I told it to fetch and write all available data. So, it should be safe to run on a collection. It requires your collection to be organised by artist, and it writes the NFO file (which is actually XML) and any JPEG and PNG files to the artist's directory. I just wanna browse artists with photos, dammit!