I think something like this should do it:
FViewportClient* client = GEngine->GameViewport->Viewport->GetClient();
client->InputKey(GEngine->GameViewport->Viewport, 0, EKeys::B, EInputEvent::IE_Pressed);
I think something like this should do it:
FViewportClient* client = GEngine->GameViewport->Viewport->GetClient();
client->InputKey(GEngine->GameViewport->Viewport, 0, EKeys::B, EInputEvent::IE_Pressed);