Overview: Instead of writing a figuration (arpeggio or similar) many times, once for each chord of interest, you can write it once and write block chords, and then expand the figuration for each chord.
First, you need a segment that contains (a) a chord, and (b) one measure of figuration (arpeggio-type stuff, but it can contain passing tones etc).
That segment has to be specially marked:
* In the segment editor, select the chord and Phrase > Figuration >
Make Parameter Chord
* Select the entire figuration and do Phrase > Figuration > Mark
Selection As Figuration
Now in the main window, select that segment and every block chord segment that you want to expand, and Segment > Expand block chord segments by figuration.
A new segment (or segments) will appear. It will contain figuration on the block chords. You'll probably want to move it and relabel it.
See also Triggered Segments.