After playing her for a while, I have a few ideas to bring up.

I think the low health is ok on paper, since it seems the sword + shield combo can compensate. This leads to a problem I have though, the sword and shield recipe is a bit steep. Flint is difficult to come by as time goes on, if you accidentally break your sword+shield (i did lol) i was screwed; I broke a ton of rocks & I dug up a lot of graves and tumbleweeds, didn't get a red gem. I know that red gems drop in abudance later on from fire spring/summer hounds, but until later it's really difficult to remake your sword+shield if you accidentally break it; not to mention flint is harder to come by after you break all the rocks. This is all compounded by it can be difficult to see what % your weapon is at due to showing both armor+weapon durability.

solutions: any combination of these can be mixed & matched

-lower the flint requirement for the weapon inital crafting.

-use gold to repair the weapon, but make the gold repair a lot. gold can be acquired by giving toys/meat to the pig king and is readily available; compared to running out of rocks to break for flint (until caves and etc). this also means, if gold repairs 50%, you can feed your sword 2 gold and be certain it'll be 100%.

-increased durability of the sword, 300 hits is a lot, but for 20 flint, 5 gold, 2 gems, i think it wouldn't hurt to be higher.

-have different tiers of sword+shields, one that you spawn with & easier to craft, and a 2nd improved sword+shield that does more damage/defense + has a steep crafting recipe. i think this idea would be cool to implement on a lot of characters that start with a weapon. i really really enjoyed this mechanic on elphelt, using different weapons was cool even if it meant not using the initial weapon as often later on.

-apparently her attack modifer was at 2.00 to start? i can actually see it, unlike many other characters, she has really low health, no range, and doesnt leech life. some other mods give a ranged attack(s) for a lot of safety, some give life, some life-leech/steal, but momiji has low life + melee + no life steal. the only extra defense is her speed and if you have the sword+shield on, and this limits you to having to use the sword+shield all the time to get her specific benefit.

imo one of two things should be done

keep her attack high, x1.50-2.00 mod
increase her health a bit, 100 seems fair
let her leech life

-in my opinion, removal of a gem requirement, i don't see why there should be such a rare/difficult to find requirement, should you mess up and break your sword+shield early on. a compromise could be to make it a blue gem and only take 1 gem instead of 2. winter hounds drop it much sooner.

positives!
- custom dialog makes any character amazing
- attack+defense = cool idea for an item
- i ♥♥♥♥♥♥♥ love fast characters and look forward to more (slower than default movement speed characters... should be BURNING IN HELL)
- i think this is a given at this point, but the art is good. it's seriously good, all the mods you release have great art; it's a given each time you release one, but the art is great.
- the hat is pretty good, i like how you still have to make a decision to take it off for warmth/defense

great job as usual