It's nearly trivial to modify a typical 3x3 stickered speedcube into a puzzle functionally equivalent to the slightly more difficult Void cube: just pop off its center caps (exposing the tensioning screws). (Beware that traditional Rubik's brand cubes do not have removable center caps, so this mod cannot be done to it this way. It follows that one cannot adjust the tensions of Rubik's brand cubes either.)
More irreversibly, one can remove the center stickers. (Though removing the center caps also becomes irreversible if you then lose those center caps, which is easy to do.)
This probably won't work for competition because subtle marks (e.g., rotation angle of the tensioning screw head) could distinguish the centers, helping the solver choose an orientation of centers that avoids a parity problem at the end.
This mod also works on some stickerless cubes, e.g., Qiyi Warrior W, and tiled cubes, e.g., Shengshou Gem and Shengshou Tank. (Note that to remove a center cap from the Shengshou Gem, put a fingernail under the corner of the center cap, not the middle of the side of the cap the way other cubes do it.) This mod looks especially nice on the Shengshou Gem because its inside color, the color of the cubie underneath the cap, is black as opposed to off-white (as it is in the W and Tank). Off-white looks similar to a white face. This mod does not work on stickerless cubes such as YJ YuLong in which the color underneath a center cap is the color of the cap.
Incidentally, the tiled cubes can do many of the mods doable on a Lego Rubik's cube. For example, pull off all the corner tiles and center caps to yield a cube with only edges. Not only is parity possible as in the void cube, but one can also solve it to not the traditional color scheme: e.g., checkerboard if the tiles hadn't been removed.
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