I'm not as familiar with Field Maps as I am with Survey123.
In the ArcGIS Survey123: Modeling Inspection Workflows from the 2022 Dev Summit, it describes how you can pull down related records from previous inspections as read only. I've also watched this 2021 video, ArcGIS Field Maps: Enabling Asset Collection Workflows Is it possible to view existing inspections as read only in Field Maps? And be able to add new inspections?
