Usually I too enjoy how Hiro reuses character designs cause its a nice homage to the previous series. However Elise and Rebecca are Way too similar in both personality and design. Shiki also pushes the borderline
Rebecca looks like Lucy and acts like 90% like her to the point they seems like the same character to me. The whole bath scene i thought it was lucy there cause they were looking and acting the same.
Elise is a little more cocky and less Strict than Erza but still has most of erzas quirks and attitude. Even her tattoo is in the same place as the fairy tail one Erza has lol.
Shink was close to being too much like natsu too but him being less hot-headed helped him not be too similar.
Anyway, I like the homage but i think Hiro should make them more stand out more on their own.