Another bad chapter for Yamao4nakama. But on the bright side, a couple tiny points for Yamao4Momo. They're even similar in how they both gained their df powers, lol. As for her straw hat candidacy:
1. Yamao has a mythical zoan. This adds desperately needed uniqueness to her character so that can be seen as a positive. But on the other hand, it could also be seen as a huge negative.
This same logic can apply to all the crew's df users. Oda gives them seemingly weak, creepy or otherwise undesirable powers but then makes them seem really awesome through his creativity. Neither the gomu, hito, hana, nor yomi fruits would be on anyone's df wish list. By complete contrast, Yamao has what's likely to be a Kirin mythical zoan. Kirin being the king of mythological beasts. A df with a special power sought out by the world's strongest creature Kaido himself. It seems far more Oda's style to give a straw hat a humble devil fruit and then make it awesome from then onwards.
2. If Yamao really does have the Kirin df, then it's highly unlikely Oda would make the only two zoans on the crew both have a deer theme associated with their transformations.
3. Ability reveal was very underwhelming. The design not only feels highly unoriginal and just an uninspired Sulong clone, but it's ugly af. Granted, that's just my opinion. What isn't however is that Yamao's "hugely awaited" df reveal wasn't even the focus of the chapter. Franky vs Sasaki was. Take Carrot's Sulong for example. She had a full chapter dedicated to her, people commenting on how amazing the design was, a scenario specifically created to let her shine, we saw her transformation in detail, and she had the chapter named after her. Yamao got none of that, only 2 pages slapped onto the end of a Franky highlight chapter. Oda could've kept her design in silhouette for the cliffhanger and then revealed it properly in the next chapter like he did with Kaido:
Although the df itself is a very powerful ability, it was not given the respectful introduction you'd expect for a future MC.