Is there any way, in GIMP, to set the color of a paintbrush to be a gradient, the first color at the beginning of the stroke and the second color as the end of the stroke? I found a help page from 2.2 which implies that it was possible then, but the UI elements don't seem to have equivalents in 2.10 and 2.10 docs don't mention it. A layer with a gradient using the brush stroke as a mask does not do anything similar to what I'm trying to achieve.
Specific use case: I'm adding various climate layers to a (fictional) world map image. I'm trying to add wind lines in a way that makes it obvious which direction I drew the line. I will probably be drawing around 100 of these, so any solution needs to be do-once-use-often and cannot assume that the gradients will be in the same direction across instances.