My favorite Spherical Minecraft-like gamedev project is PlanetSmith [0], which uses hexagonal voxels (and a few pentagonal voxels). The devlogs are very well produced and I highly recommend checking them out.
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> You can even reduce the amount of visible distortion by restricting players to a portion of a shell, so they never see the full difference in block size at its top and bottom.
> From what I can tell, this seems to be the approach used by the upcoming game PlanetSmith for its hexagonal-blocky planets.