Conditional formatting Clustred Column chart with two values

I have a clustered column chart with two values in the Y-axis. 
I want the second value to have the color as:

If begger than 0 then Green 
If smaller than 0 then Red 

But there is not conditional formatting available when there are two values in the Y-axis. 
I have already searched the community and couldn't find an aswer. I see that people struggling with this since 2017. 
Anybody has maybe a workaround?