Yes, you’re right, it might not be possible. Essentially what a report does is list out each item ONCE FOR THE COUNT. What your question is asking is “hey can I count this item once for each metric -- so, a total of 3 times. Once for the yes, twice for the two no’s, for example.”
The way workfront reporting happens to work, you need to find an object that represents what you are trying to count, only one time. It’s a pity that each metric isn’t being presented by a task for example, because then each task = one metric only, and you could make a count per portfolio of all the metric 1, 2 and 3 tasks instead.
As it is, I don’t see any potential in any of the workfront charting functionality (you could maybe set up some total count calculated fields -- i.e. count all the yes’s, count all the no’s -- and add them up across projects, but don’t think you could chart both on the same chart. You could put a no chart and a yes chart side by side. You could take it into canvas dashboards and do KPI charts). Other than workarounds, you’d be better off taking this offline into excel or powerBI instead, in my opinion.