Board Thread:Episode Discussions/@comment-25319479-20180719110008/@comment-25122992-20180727081752

There were no traces of Lightning Release in her attacks. Moreover, the databook entry of Gentle Step Twin Lion Fists says nothing about any chakra nature applied to it, just that the technique is a secret Gentle Fist jutsu (while we know that Gentle Fist was never used with any chakra nature at all).

Plus, as @Naruto Tailed Beast Mode already stated, if Naruto trained to create a technique with a chakra nature, it doesn't necessarily mean that Hinata had to do the same. The point was not the chakra nature training, but Hinata's wish to catch up to Naruto by mastering a high-level techique.