Honestly I doubt there is much of a connection here.
Kindreds design comes from merging the concept of lamb&wolf with Yin&Yang and death(originally intended to be life&death).
With the yin and yang comes already the dark/white color scheme that is similar,the masks are also a result of that(possibly combined with princess mononoke reference).
Giving wolf a more pet-like role was mainly because they had trouble making a real double-champion.His more mistlike appearance is a result of giving wolf a head,but no body,while giving lamb a body but no visible head,so there is again this yin-yang theme.
And honestly the similarities more or less boil down to:
White girl with animal motif(and mask) and dark wolf companion.
I feel bad for Chiara that people now think of her artworks as fanart for kindred,but stuff like this happens all the time,I mean 2 people who never met managed to invent "dennis the menace" at the same time
https://www.plagiarismtoday.com/2010/10/18/the-odd-case-of-dennis-the-menace/