DAX Optimizer currently analyzes DAX measures, KPIs, calculation groups and row-level security (RLS) filters.
It does not analyze DAX expressions in calculated columns or calculated tables.
Calculated columns and calculated tables do not impact the query performance as they are evaluated only during data refresh.
Visual calculations, also, are not part of the semantic model. They are stored locally in the report and are not available in the VPAX file. However, visual calculations do not usually generate performance issues because they work on a copy of the summarized data prepared for a visual.
For calculation groups, unlike other objects analyzed by DAX Optimizer, only issues are reported. Metrics such as relevance, impact, and executions are not included. To estimate the cost of the calculation item, you can use the workaround described here.