I don't really think
Wendy goes with the other two.
Wendy is quite dated and a little old fashioned, whereas I think
Evan and
Nathan are more modern (not in a trendy way, just more modern than
Wendy. They don't sound ridiculous together, but they don't really match either.
However,I do like the name
Wendy and it might be nice to see it used on a young girl for once.