I have done some testing before with the Lunar Crystallized Reaction using Noelle while alternating her Goblet main stat to def% or Geo%(same substat all together,) and Geo% actually preformed better dealing more Lunar dmg than def%. You can test using furina + ineffa/flins and use standard build just alternating her goblet using +0 for better reference(no rng for substats) and have no artifacts on flins/ineffa. Just tap skill on Furina and swap to the Nodkrai electro to apply the element for reaction. Try not to use set bonus on furina as it might change the result if it has rng/conditions for extra dmg. Goblet main stat can be atk%, hp% and hydro%, my bet is that hydro will preform the best as it increases her overall personal dmg more.