I do not have a release date for the IQ Panel 5 yet, but I can confirm that the latest version release for the IQ Panel 4 includes support for the new PowerG Plus line of sensors. A link to the latest version release notes is below.
PowerG Plus sensors are new and do not appear to be widely available yet. I’m not seeing availability for most of them with some Google searches.
What is the time frame you are looking at to get started?