Hey there, I could solve this problem tediously, but I'm looking for an easier way to do this.
Lets say I have made an isometric graph (to be duplicated more than 50 times in a chart)
The chart depicts temperature fluctuations with Red being the highest and Green being the lowest, in the middle it's yellow.
I want a gradient to show that for all the graphs so I made an adjustment layer to have sort of a overrule gradient effect, turns out this wiped my lines clean off as well, I had used 4-Colour Gradient effect, for those that are wondering.
The parts in red are the parts I want the gradient on , basically the whole thing, it's just when I slap a gradient on to it, the effect recognizes it as a full singular image and erases the lines away, having filled by the gradient itself, this doesn't make it look isometric anymore.