It loses some games to Stockfish 13 and 14, and Lc0 - rarely at slow time control, and more often at blitz and bullet (actually, it has losses all the way down to Stockfish 9 in blitz).
Partly because of the way it tries to search more widely to avoid tactical traps, it can also be a little sloppy in holding advantages or minimizing losses (this could use some more work and tuning). This ends up making it a little drawish, so it loses less than you'd expect to Stockfish 14, but also doesn't beat up weaker engines as well as Stockfish 14 does.
You can see some of this in the raw tournament results[1]. At 40 moves per 15 minutes, repeating, each engine draws with the ones above and below it, but starts to win and lose at a distance of 2 or 3.
At 5+3 time control, ChessCoach goes 1-0-29 vs. Stockfish 12, but Stockfish 12 is better at beating Stockfish 8-11 than ChessCoach is, so CC ends up between SF11 and SF12 in the end.
On Lichess, where there's no "free time" to get ready for searches, ChessCoach's naïve node allocation/deallocation makes it waste time, and means it can't ponder for very long on the opponent's time - a big opportunity for improvement (it needs a multi-threaded pool deallocator that can feed nodes back to local pools for the long-lived search threads). I think it's also hitting a bug with Syzygy memory mapping that Stockfish works around via reloading every "ucinewgame" (which I don't trigger on Lichess). So, overall, its performance on Lichess is worse.
Also, you can't read too much into this data - very few games, and no opening book.
[1] https://chrisbutner.github.io/ChessCoach/data.html#appendix-...