used command is:
give @p stone_axe{AttributeModifiers:[{AttributeName:"generic.attackSpeed",Name:"generic.attackSpeed",Amount:-2.4,Operation:0,UUIDLeast:1,UUIDMost:10,Slot:"mainhand"},{AttributeName:"generic.attackDamage",Name:"generic.attackDamage",Amount:6,Operation:0,UUIDLeast:11,UUIDMost:20,Slot:"mainhand"}]} 1
the command changed. sorry.