Blender 2.8 has yet to notify the add-on developers to make it compatible with 2.8.
If you see a message stating "Upgrade to 2.8x required" it means the addon was made for older versions of Blender 2.7x and does not work for newer versions.
Unfortunately there is very little you can do as a user to fix it.
Check the author website for an newer updated version, or ask the developer for an update. Most addons require small changes to adapt and can be easily updated.
If it is a commercial addon you payed for try contacting support for an update. It is often in the best interest of the owners to make it work in the latest release.
Otherwise roll up your sleeves, learn Python, and update the addon yourself by coding in the required changes in. Most addons require only small adjustments.
