I appreciate that’s a wordy question. Hopefully, this pic will clarify.

A and B - green polys, low detail at edge - are a dataset I am using to run into a SpatialFilter to determine areas of intersection with the more detailed dataset in pink (amber where there is overlap).
You can see that part of the upper example polygon I have coloured part of area 1 in blue, and sits mostly inside A. The smaller, black part of 1 sits inside B.
I want to join the entire area of the intersected polygon fully to the feature from the green dataset that contains the largest part of it - in this case, to A.
Any ideas how best to proceed? I currently foresee:
- Check for intersection of area 1 with areas A & B
- Calculate area of overlay
- Test for largest
- Join all of the area of 1 to A
Feels like there may be a fair few transformers involved. It’s a national dataset. Just trying to figure out how best to do it. In Esri, I think there might be a simple option to ‘join to largest’…? (Not that I want to jump out of FME)