>Yokai core and yokai shift.
Yokai Shift isn't great right now, yes, but it's still very useful. If you think Yokai abilities aren't good, though, you are using them wrong. Ok so yeah some DO suck, but there's several that are very useful. Use them to compliment your melee, don't rely entirely on it.
Reread what I said about omnyo. Literally any build can use the passive I listed. Omnyo skill points can be earned by finding Omnyo Locks consumables, or by using Fire Talisman type items. 2 or 3 points gets you +10 resist to dark realm. That's it. No magic investment needed, barely any work to earn, and its passive so its always active.
The other passive I mentioned isn't even in Omnyo. Its in Shiftling, which you you earn points for by collecting soul cores. 4 points needed. One point to gain access to it, 3 points into the passive itself. It is, again, always active, and reduces the penalty for being in the dark realm by 30%. Combine both those passives and dark realm becomes so much more manageable.
You can't ki flux dodges, no, but you should always flux ki spent on attacks, as ki management is important in dark realm. You also get bonuses for perfect ki flux with the right investment of Samurai skill points. Low stance bonus reduces the ki cost of your next dodge by 100%. Mid stance reduces the ki cost of the next block by 100%. Another skill will greatly increase ki regen whenever you purify a yokai cloud with a perfect flux. And yes, both bosses in the beta creates these zones, even in the dark realm phase.
You have the tools to deal with the dark realm. It's up to you to use them. All of the skills I listed are also found very early in their trees, with literally no stat investment required to access or use