So not on a server in my own world, I would like to have sharpness 5 knockback 3 and flame and pillage 3 because I don't get any more levels to enchant because the nether is empty, besides you can only enchant 5 times on a sword and that unfortunately not possible, is there a way to make his slide sword op?
I don't understand exactly what you mean, but go to mcstacker.net and generate a / give command that gives you such a sword.
Does that work with Cheats Off?
No
With the Java Edition you can open the world in LAN to allow cheats for a short time, but with Bedrock I have no idea.