Involve as many stakeholders as possible to get different perspectives from the sectors. This exercise is also recommended when different cities are participating, so they can get mutual inspiration regarding the different measures.
For mitigation, you can do the same exercise but looking e.g. at the GHG inventory from local government / community areas (template M2, M3) / For adaptation you can look from the perspective of hazard/impact, risks or adaptive capacity perspective (A2).