You can change the bar colour by using a disconnected slicer, a measure, and conditional formatting.
In this small example, I made a [Disconnected Products] table and used it in the slicer. Then I used the following measure to harvest the selected value and set a HEX code:
Selected Product Conditional Formatting =
VAR _SelectedProduct = SELECTEDVALUE( 'Disconnected Products'[Product Name] )
VAR _Result = IF( MAX( Products[Product Name] ) = _SelectedProduct, "#FF0000", "#0000FF" )
Finally, I set the data colour on the bar chart to the new measure.
Curbal actually did a video last week that, among other things, illustrated this technique. See time index 5:10.
Hope this helps.
eDNA Forum - Set Bar Chart Colour by Slicer Selection.pbix (372.9 KB)