The add-ons I use are part of my workflow so I'd like to know if I'll still be able to use them with Blender 2.8.
But if nobody is sure, is there a way i can find out?
No, most 2.7# addons will not be compatible with 2.8# versions of Blender, and will require explicit porting and updating.
The Python API has changed in ways that break compatibility. It has been improved and expanded to allow further integration, more features, and better workflows and these would make old addons not work in newer versions.
All the addons that come with Blender, and that still make sense to have (e.g. not the Layer Management addon because Layers don't exist anymore), are planned to be updated and made available in the stable 2.80 release.
As for the addons that you might have downloaded from somewhere else, the best person to ask is the developer/developing house: check on their websites, twitter, github or gumroad: have they announced their plans?