Display with non-square pixels

I am trying to support device with non square pixels.
Display has aspect 16:9, but resolution is 1920x540. Even aspect is 16:9, image is rendered in 32:9 aspect, because it keeps pixel aspect 1. Constrain aspect is not solution too, because it adds only black stripes and keep pixel aspect 1.

Is there easy way to force pixel aspect different from 1?

I followed this path, but because ULocalPlayer::CalcSceneView() is virtual in 4.16 engine I implemented CalcSceneView() in derived class instead of reimplementing Draw() method.