This is from
www.plagiarism.org, as not to make it appear that it was my original idea . . . .
They said that according to certain sources . . . . Plagiarizing is defined as "to present as new and original an idea or product derived from an existing source." In my opinion, the works in question would not exist in their current form without her having "copied the composition and colors" from another artists existing work in her chosen medium. If "plagiarism" is not an appropriate term, then "copying" would suffice. In other words, her works are based on (derived from) someone else's work. Copyright violations are a different subject altogether, and that is not what we're talking about here.
Food for thought.