shikamo shikome da しかも醜女だ
On top of that, [she] is a shikome.
shikome... shikome? しこめ･･･しこめ？
(...)
minikui tte koto ka? 醜いってことか？
[It means] ugly?
shikome 醜女 is spelled like minikui onna 醜い女, "ugly woman." It's also a name of an ugly female demon in Japanese folklore.
dare ga? 誰が？
Who?
This isn't a dislocation. It's an omission: who [is he saying that is ugly]? You can tell it's not a dislocation by the fact there's no verb for "to say" in this context, so it's omitted, not dislocated.
Nezuko 禰豆子
(Tanjirou realizes this guy is calling his little sister ugly.)
The ne of Nezuko should be 礻爾, not 禰, but 礻爾 is an archaic kanji. There's no way to type it. And in modern Japanese you just use 禰 instead.
shikome no hazu nai darou!! 醜女のはずないだろう！！
There's no way [she's] ugly, [you know]!!
yoku mite-miro, kono kao-dachi wo よく見てみろこの顔立ちを
(dislocation, again.)
kono kao-dachi wo yoku mite-miro この顔立ちをよく見てみろ
Try taking a good look at [her] face.
kao-dachi 顔立ち
Facial features.
machi demo hyouban no bijin datta zo, Nezuko wa 街でも評判の美人だったぞ禰豆子は
(dislocation, for the third time in the same page.)
Nezuko wa machi demo hyouban no bijin datta zo 禰豆子は街でも評判の美人だったぞ
[Even in my hometown], [everybody agreed that] Nezuko was [a beautiful girl].
hyouban 評判
The reputation of something, according to critics, reviewers. A restaurant that's known for being is said to have a good hyouban, or a high hyouban, it's thought highly of.
hyouban no bijin datta 評判の美人だった
Was the reputation of beautiful-person.
Was agreed (by most people) to be a beautiful-person.
Was known to be a beautiful-person.
machi de 街で
In the town. This is a scoping de で particle. In this case, Tanjirou is probably talking about the town he lived at, his hometown.
