Well, had to come to answer myself. UE4.23 ships with vulkan-1.1.106 which is embedded with UE4.23 itself. So it all supposed to work out of the box unless:
- you don’t have video drivers that support Vulkan - just install your latest
- you have made local installation of different Vulkan SDK version and added path to it into your bash.rc or profile. This will override Unreal paths and will break the build. More on it here: F:/UnrealEngine-release/Engine/Source/Runtime/VulkanRHI/Private/Android/../VulkanLoader.h(6,10): fatal error: 'vulkan.h' file not found - Rendering - Epic Developer Community Forums
I installed SDK from LunarXchange (you’re looking for 1.1.106 version), but I cannot say was it essential to be installed or not now.
And yes, UE4.23 works on Ubuntu 16.04.