Hi @ngdnam88,
I'm not aware of a way to do this. The only thing I can see is to have the folowing workflow coded :
1. Select a chainset dimension, by clicking near the desired dimension.
2. Get the point2d of where you clicked with the mouse one 1.
3. Loop through the chainset dimensions one by one and compare with the point2d created on 2.
4. Get the closes dimension
5. Add the sketch symbol to this dimension.
To me this looks complicated, but it can be done.
An easy fix to this issue is to use the other chainset dimensions tool that produces separate dimensions :

Thus, avoiding the issue of getting a collection of dimensions.
Kind regards,
FINET L.
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