Use this to export your assets. The issue with Sketch itself and most other plugins is that it neglects invisible layers while exporting. As a result, invisible bounds do not work.
I even tried to decrease a bound's opacity to 0 so to try to trick Sketch into exporting it. But Sketch's native export isn't so naive.
You might see a horde of plugins of Sketch that help in exporting assets for Android easily. They might reduce the steps involved, but it doesn't solve the bounds problem.
This one does.
It allows you to export assets for iOS, Android and Windows for all resolutions while keeping the bounds intact.
Saves all that artboard efforts.