Add consistent custom colour mapping to all Power BI charts and legends

[DrCoffee]

I'm kind of baffled this isn't a feature because it seems so fundamental to data presentation. If I have a report with multiple visuals, I should be able to assert consistent colours for the same category across the report. 

Manually doing this is not a valid solution, because you cannot manually set valid categories in dynamic datasets when those categories don't happen to have data in the current snapshot. Having custom mapping really is a must for good, consistent data visualisation used for regular reporting.