It is just geometrically impossible to take something like these random Voronoi cells on an anticlastic surface and make them planar while keeping connected along their edges, and also keeping the approximate surface shape, maintaining the same mesh connectivity and approximate cell shape.
That’s not a matter of software, just mathematics.
You can create a mesh of planar hexagons and other polygons, but they would have to be drastically different shapes than what is shown in your original image (indeed many of them would need to be concave). Very likely even just by changing the shape of the cells it would not be possible - you’d need to modify their connectivity too.
If you go down this route I’d say it probably ends up as a regular grid of ‘bowtie’ shaped hexagons, something like this:
This is something very different from what is shown in the initial image here though, which is why I’m recommending to clarify exactly what it is you are trying to do here.
If the important thing is the look of the randomized Voronoi cells, then perhaps better to think about a different construction technique that doesn’t require the panels to be planar, or where they don’t need to meet exactly edge-to-edge.