I don't think it will be mute. Their designs reflect that they goes beyond Lunarian genes. Kind of mix breed with worlords skills/strength + Cyborg + Lunarian traits.
This goes beyond what King was capable of imo
Also, why VP used Lunarian genes? It could be that we haven't see what Lunarians really were capable of when king fought Zoro.
But you're forgetting that they, despite having Lunarian genes and abilities, shouldn't be that experienced with their abilities considering their age. It is also highly likely that they don't have Haki either.
On paper, they seem op but I'm sure that there's some negative aspect about them, ie the lack of Haki.
Now when it comes to King, let's not forget that King has Haki; his CoA also matched Zoro's. So it's not just his Lunarian power. Plus, Seraphim have Lunarian + Cyborg body but King also has his ancient zoan fruit which drastically boosts his durability and physical power as well. A lot of King's feats are not solely due to his Lunarian genes, it's his own skillset/strength as well. Tempuradon is a result of his own strength + DF and it destroyed multiple big mountains.
It would be interesting if we see more what Lunarians can do but wouldn't King technically be able to replicate the same abilities, especially since he's an extraordinally skilled Lunarian?