Fendue is the past participle of fendre, the French verb to split.
It is usually seen in heraldry rather than in a Christian context, and therefore we follow the heraldic custom of using the French term rather than the English Split Cross.
A distinction between this and other disjointed crosses, such as the Trononné Cross which has multiple cuts, this Fendue Cross is invariably split into just two pieces. (Imagine swinging an axe on a log; it will only split into two pieces from a single cut.)
As with all crosses, there is no universally accepted meaning, and you are at liberty to interpret this cross in any way you choose.