He's got the talent, i don't think he's got the mentality. Might end up a poor man's ribery.
Ribery was a beast between 2012 and 2014 though. Top 5 in the world easily. Hazard would do well to reach that level
That timeframe mostly coincides with Heynckes' tenure at Bayern, whose style of play suited Ribery very well. During van Gaal's and Guardiola's spells with their stricter rules on offensive movement, he had a much harder time finding his game. Injury troubles were a large factor too, of course. But when I saw him this season under Ancelotti, he looked lively again, despite his now usual fitness issues.
So I think that a lot of the things that are so often reduced to 'form', 'attitude', 'mentality' etc. have more to do with the question if a certain setup actually suits the player's strengths or not. If it puts him in positions that bring out the best of his game. A players' overall quality and personality doesn't change drastically in just a few months, but the general tactical cohesion of his team may very well do. Just compare Pedro last season with Pedro this season. Or David Luiz during his first Chelsea spell and now under Conte.
I don't think Hazard ever had a really fitting environment in the past, neither with Chelsea nor Belgium. Despite his massive individual skills, he is a team player first, an individualist only in second place. Much more Spanish in style than (classical) English.
But even when Chelsea were good in the PL under Mourinho, they played something between uninspired and negative football in Europe. Conte's 3-4-3 is the first manifestation of a Chelsea team that I can see having constant offensive fluidity in big games in Europe, which is the environment Hazard thrives on. Same goes for Martinez' recently installed 3-4-3 for Belgium, which looked good offensively so far.
So I'd wait for another season (because of CL participation) & the WC for a judgement.