Would trans hydride ligands on a metal complex be beneficial for a catalyst?
In alkene metathesis you need large ligands that direct the stereoselectivity of the reaction, and a hydride ligand is very small.

Also for hydrodefluorination I don't see an advantage of a trans hydride ligand on the catalyst. cis hydride ligands could be beneficial, as they then take the place of the fluorine atom on the substrate.