Where can I find output requests related to comfort models?

In the libraries workspace

You can find comfort models related output variables like PMV and PPT assigned to the People Type in the Interna loads object:

In the Buildings workspace

Be sure that you have properly defined one or more thermal comfort models on the People objects. Go To the Buildings workspace -> Zone Grouping -> Edit Template -> ... button right next to the Occupants. YOu need to select at least one Thermal Comfort Model and the related properties such as Work Efficency, Closing and Air Velocity Schedules.

For more details on those models and the people object properties see: https://bigladdersoftware.com/epx/docs/9-2/input-output-reference/group-internal-gains-people-lights-other.html#people