Hi there!
Well, you can kind of achieve this with this plugin, by assigning an exclusive font to the Window_Gold and using a different color for it.
But I don't believe this is the best way to do that. Because both the Gold currency and the Gold value would be the same color. So I guess if you want to change that, you can use my Global Text plugin, and just change its color by using an escape code on the database.
https://hakuenstudio.itch.io/eli-super-text
