You aren't allowed double empowered finisher, nor empowered finisher + another finisher mod on class items. This was patched a while ago - trying to equip a loadout with either of these on its class item (yours looks like it has special finisher + 2x double empowered) will force a weasel error. If you have the class item with the mods equipped already in your inventory, you can manually equip it but you will need to change it to something else in the loadout.