I confirm the color profile workflow is indeed deprecated, so I don't recommend using it anymore.
In the case of Unreal, switching the Tone mapping setting to ACES should be enough. I don't recommend enabling OpenColor IO (OCIO), as this will complexify greatly the workflow inside the application.
The ACES curve we use is missing some update, like the bright blue value becoming purple, but otherwise it should be close enough. I'm not aware of a need to shift/apply a gain to the transform to match Unreal viewport.
By the way, when creating a project you can use the Unreal Engine template, it will configure it with the right settings to help match Unreal viewport.