Replacing a line in an existing polygon

A couple of different options.

Use the Snipper to remove the boundary between identified indexes. Use an AreaBuilder to rebuild the polygon with the remaining boundary and newer line.

Use the PolygonCutter custom transformer.

Use the AnchoredSnapper in SegmentSnappingMode with the line as the anchor. You may need to densify the polygon first.

Use a pythonCaller to manipulate the polygon boundary curve.

@melanied Do you have a small example dataset you could share with the community?

Thank you for your answer : Snipper and AreaBuilder seem a good solution. I succeed in replacing a line in a polygon with these transformers. The reality is that for each polygon I have generally more than one line to replace, I have to iterate and it's not easy to update the initial indexes. If you have any suggestion for this part, I am listening !