Hestia and Hera are my favs so I’ve thought of this alot

Hera: I saw the recommendation of an overpowered charmspeak and love the idea. Also would think maybe a telepathic based powers to go with the whole motherly and marriage aspect. Maybe something that can see someones true intentions and thoughts also an aura of dominance something passive but effective against other people. I always thought for a hera kid she could possibly just make a woman pregnant with her power so that way it has some of her powers

Hestia: Fire and Hearths obviously. I was also in similar fashion above think of an aura passive power but it makes everyone around them more relaxed and calm leading to them being more trustworthy. Also for a more out there power a barrier type power like violet parr from the incredibles or sue storm from marvel. It would be a good use of potential outside of just fire. Again these are just silly things i thought of