If header text could utilize a function (such as LOOKUP) that returns a value from a table, you could then have a table with columns named after the top n products.
It looks like the following ideas could be combined and perhaps higher votes. Please consider voting for multiple of these until they are consolidated... + Dax calculated measure name / Dynamic column headers https://ideas.powerbi.com/ideas/idea/?ideaid=15baaa8c-5cb2-4962-90c8-01b2ecfb358a + Dynamic column header in Power BI using formula or expression https://ideas.powerbi.com/ideas/idea/?ideaid=d388d4f7-2eb4-4791-818c-9b8da6a27183 + Dynamic Column Headers in Table/Matrix https://ideas.powerbi.com/ideas/idea/?ideaid=8d4b32ae-f572-eb11-8ced-0003ff454088
