In 3D, we have a total of 48 different combinations of space coordinates to choose from:-

2 handed (or single axis flipped) systems x 3 axis x 4 (90 degree possible rotations around each (generally)) x 2 (possible 2 flipped axis variations on the same hand same rotation) = 48 possibilities.

There are 6 ways to notate xyz in a file but this would essentially replicate one of the 48 possibilities simply converting it from one possibility to another.

The functions below will only cover converting the 6 basic types (2 handed (or single axis flipped) systems x 3 axis) to Y-Up Left Hand system used by unity, so discounting the one that unity uses equals five conversions & one non conversion, also presuming all notation is written x,y,z irrespective of direction.

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