The relation ‘Attitude’ should be similar, but perhaps no attachment widget. This feature definitely works in QField (but not polymorphic relations, although there is a workaround). In the meantime, common issues to check are: are primary and foreign keys the same data type? Is the primary key (uuid) populated?
https://gis.stackexchange.com/questions/475050/setting-relations-in-qgis-not-working-in-qfield