The object list views were not designed to use the Project Management Work Effort Unit of Measure setting.
There are other places within the application that can be configured to display these aggregated values at the project level for comparisons between projects.
The following system portlets can be configured to display these values in hours, days or FTE:
Home, Resource Planning, Organizational Demand, OBS Investment Aggregation > drill into the OBS Investment portlet (System Provider = Aggregation Investment List)
Main Portlet Name = OBS Investment Aggregation
Portlet ID = projmgr.OBSInvestmentAggregation
Then drill down into the OBS to get the list of investments shared by the OBS.