Search for an Compare (tool,app) that only compare lines with regex

I wanted to ask if anyone knows a tool (Windows) that compares text files but only considers lines with Comments? Comments that serve as a kind of marker/label.

Item: item1 **not compare
Material: mat1 #-quick jump 1 **compare
Item: item2 **not compare
Material: mat2 #-Jump label 2 **compare

I have tried several tools, but none of them offer such a comparison.

Tested: meld, winmerge, guiffy, ExamDiff, and ecmerge.

All these tools offer an ignoring of RegEx, but no comparison of just these