We're not even talking cel-shaded CGI. It's full US-style plastic CGI, like lots of other kiddie shows. The characters are egg-shaped cars. Some look like hedgehogs. (Two of those sing a duet.) Some look grumpy and industrial. The one who's almost certainly the hero is yellow and wears Biggles-style flying goggles.
It's a Chinese co-production. I watched a random episode. It looks fine and I'd have probably kept watching if I'd been eight years old.
One-line summary: silly but imaginative time travel story, mostly set in Ancient Greece
The most interesting thing about this show is that it's based on a manga by Mari Yamazaki, the Japanese mangaka who's been living in Italy for ten years and also created Thermae Romae. (Besides Japanese, she also speaks English, Portuguese and Italian.)
It's proud to be silly. The ancient Greeks are done as stop-motion claymation. Modern Japan is portrayed a bit like the hand-drawn bits in the 1976 Paddington Bear TV show. The theme song is the "William Tell Overture", sung by two blokes going "dadadada". The end song is a comedy piece written from the viewpoint, ethics, morals, etc. of the ancient world (and the one in ep.2 is a different one).
Demetrios is a vase painter in Ancient Greeks whose boss wants him to enter the Olympics. "Be a hero! Make money! Honour is money!"
It can be both amusing and educational. Demetrios's historically authentic view of the Olympics is very, very different from ours. It is, though, basically a string of gags. I'd have probably watched a 12-episode series of it, but 24 is two hours.