I'm still trying to complete Odyssey, I've completed the main story and am going back to get more power moons, currently at 450 - but I keep getting stuck on the Koopa Troopa races, any advice?
Follow whoever wins to learn their route. The Cascade 2nd race was the hardest one because the gold one pulls off a hard ground pound cap dive jump combo but you can still win by going just to the left of where he jumps and going up to the right of the chain chomp. In the lake world get to the fish as fast as possible and head to the left of the area with the shops and take that flower at the surface up.