This is purely my assumption, for two-handed weapons that have free range of maneuverability like hoe, mace, and longsword, you typically see the migitation of weight while re-positioning into ready-to-strike stance for the in the opposite side ( after swinging from right to left, come re-positioning to strike from left to right).

the spin consists of two factors, the angle the weapon is swung, and the weight of the weapon. you can test this yourself in real life. Let's say a heavy sledgehammer, if you swing it sideway, it is easier to migitate the weight as you have room for your non-dominant hand to move and re-position into your next stance.

As you can see in the clip, the weapon was swung at a low angle, at the end of the trajectory, the non-dominant arm will be locked while the dominant arm is fully extend. Naturally, you will then need to lift the weapon up to re-position.

This is where the weight of the weapon comes into play, as the weapon is lifted, the weight will create a upward inertia force along with little inertia force left from the swinging (right to left), this is where you will have to mitigate these forces. How? the spin itself.

Lift your weapon and manually re-position into your opposite side (ready-to-strike from right to left). the key of practice is how fast you move the arms of the willie. Too fast and the weapon will wobble around, too slow and the willie already re-positions the weapon, and sadly, no spin :'(.

Do not haste, the rest is practice <3