Hinata is a Homo Sapien Sapien. Thus she is not an earthworm

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OT: The relation is about the same as any Uzumaki (likely), Senju, Uchiha, or Hyuga (likely).
1. Kaguya
2. Hagoromo and Hagoromo's Brother
3. Indra, Ashura, any children of Hagoromo's Brother
4. Uchiha, Senju, Uzumaki (likely), Hyuga (likely)
That's about it. The best relation you can say is that she is a key bloodline starter. Being from the main branch, Hinata/Hiashi/Hanabi would be the most closely blood related Hyuga to Kaguya assuming the Hyuga are related (which is likely).
Other than family relations, the have a few subtle similarities.
1. Byakugan
2. Noble Status
3. Women
4. Hime style cut (at least at the back end for Kaguya).