I would say you are right and that Earth Style Enhancement would be better seeing as Wooden Style Universal Nature hits a random target which could be either a immune target / dodge target or even a clone and takes their chakra / immobile. This skill only goes off with a shield so if you lose it then there's no point to it. It c*so backfire and immobile you instead or any of your ninjas if they are using kurenai / fire main. So i would say Earth Style Enchanment would be the better choice.

Hi!

It would really depend on what lineup you use. Since Edo Deidara and Roshi are both Earth Natured, they do benefit from "Earth Style Enhancement", however, note that the Earth Style Enhancement is only for 5 turns. Edo Deidara and Roshi are both very good ninjas and gets stronger the longer the battle lasts.

I personally would recommend using "Pose of Duel" instead and potentially using the other skills in the Crimson Fist's arsenal to make better use of shields to buff ninjas. Also, "Wooden Style - Universal Nature" is a risky but potentially high rewarding move; capable of immobilizing a unit and absorbing 40 chakra.

if a battle lasts 5 rounds in gnw means something is really off.

@OP: Universal nature may be extremely counterproductive for 3 reasons: 1) can be reflected back or wasted on a clone/immune ninja. 2) when used earth main don't apply again shields, so means you are less resistant. 3) earth main has to be shielded when his standard attack turn comes to be able to use it, something close to impossible with the current available lineups, overall in gnw where you are constantly nuked by huge aoes.

The best passive for earth main in gnw, right now, as jib told you, is pose of duel because even if the enemies run a buff remover you can still hope to get back the buff as soon as your ninja gets shielded again by your standard attack or by a ninja's mystery (like kurenai's or gakido's or main's).

There's only an acceptable way to use Universal nature in gnw right now and is by taking advantage of monkey king summon mystery (the clone that you summon with earth main uses it), but still, imho, is worse than giant katsuyu or ninja dog ones for CF.