Can Sand Soldiers created by Arise take equipped Gear off other friendly units?

No, Sand Soldiers created by the spell Arise! cannot take equipped gear off other friendly units.

There is no mechanic in the game that allows a unit to automatically "steal" or detach gear from another unit simply by entering play or existing. To move an Equipment from one unit to another, you must use an ability that specifically allows for it, such as the Equip keyword or a specific card effect (like Akshan, Spiritforged).

According to Rule 744.1.b, the Equip ability is an activated ability that allows you to pay a cost to attach a piece of gear to a unit you control. If a piece of gear is already attached to a unit, it must first be detached (or targeted by an effect that specifically moves it, like Akshan's ability) before it can be equipped to a different unit. The Sand Soldiers created by Arise! do not possess any such ability.