With eMeL it's easy, and I think you can have greater control on the roadside's shape. You can do everything just with road profiles. It's just the matter of adding some more points to the road's shape and move them away from the road. Then switch within the panel to Materials and move furthest points to the moddle (drag) - add some grass material or something else you want to have close to the road. I used three (actually four) textures/materials - road in the middle, two different roadsides and grass (I just repeated the procedure from above and added one more - grass). Please observe it on picture #2.
One advice - don't add too many shape sections at the beginning, because if you change your mind about the number of points (add more) - the more cross-sections you add, the more single points you will have to correct. Also, add Material Change sections at the end - textures like to move if you touch points in Shape and you have also checked the Material Change in the same cross-section.
I found the terrain shape tool as not very accurate, especially for more dense (with vertices) places. And moving every terrain's vertex manually is a nightmare for me
You can of course experiment with horizontal and vertical randomness in road shape panel - this maybe can help in case you want to get more complex shape of roadside. Just use bigger values than in road.
Last thing - remember that adding new
Material Change sections to the road
will split it into new objects when you export. This works the same with Walls. Good thing about it is that for long tracks you will have less polygons to render at once*, the bad can be when you produce too many objects - it can harm the performance.
Shape crossections don't split roads nor Walls.
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* this is about LOD for roads, there was quite enough about it on the Forum (too much off-topic here - ask me if you want me to explain it again some day
)