Hm...actually, Fukuthrow's wings would be perfect paddles
Surprise Evo episode...?
You know I've actually thought about if this could be Rowlet's evolution, episode on one hand a part of me thinks that Rowlet won't evolve here, and on another hand part of me thinks that it will evolve here, after all it wouldn't be the first time that a evolution occurred during a competition. Also a interesting thing to note is when you look at the number of episodes between Ash's Alolan pokemon capture and the episode they evolve and it breaks down like this:
Rockruff capture episode 15: 15+22=37 Rockruff evolution episode 37
Litten capture episode 21: 21+42=63 Litten evolution episode 63
if this continues with Rowlet then Rowlet capture episode 4: 4+62=66 Rowlet evolution episode 66
now while I know that the pattern could easily break and I do expect it to whether or not it's Rowlet that breaks it is debatable as it could go either way, but if Rowlet doesn't break the pattern then I expect that Ash's 4th capture will probably break that pattern. Oh and the pattern is that if you look at Rockruff and add 22 to it's capture episode you get it's evolution episode while if you add 20 to 22 you get 42 and then if you add 42 to Litten's capture episode you get it's evolution episode so if you add 20 to 42 you get 62 and if you add 62 to Rowlet's capture you would get episode 66 which would theoretically mean that Rowlet would evolve in episode 66.
Now while I do expect that pattern to break at some point, it's interesting that Rowlet can fit in it, and Rowlet evolving in episode 66 can't necessarily be ruled out, of course it's possible that a different episode could be Rowlet's evolution episode but we will just have to wait and see.
Although that is interesting that Dartrix's wings would make good paddles.