In short, I'm not saying that Primarina's feminine appearance and the fact that the Pokémon is mostly male are a problem, but this connotation of the Pokémon being just female or mtf transgender is something that appeals to more a specific niche. So I made this masc version because I think Primarina's design wouldn't be criticized if there was another option. And importantly, I didn't exclude the possibility of evolving your poplio into the "fem" version of the Pokémon because to get my versions you would need to evolve one level before Brionne and Primarina evolve, so you can choose the appearance/form independently of the gender the Pokémon turns out to be, thus giving more options being cis or trans mtf or ftm also.
Design description: I used the "layers of scales or fins" that look like a Brionne skirt as ruffles used on shirts by macaroni, a masculine aesthetic (which was used by nobles but artists like clowns for example also used it) and in the final form that I called Primarine he loses the ruffles on the tie, and gains a high collar which represents him kind of being free and being a rebellious sea prince but still has the ruffles on the it's "sleeves" ( bare wrists) to show that it's is still a prince and has pearls holding it's collar and on the sides of it's crown made of spikes
by Downtown_Safety_3799