The Elder Scrolls V: Skyrim

is there a console command to disenchant an object?

I want to disenchant the mythic dawn robes to make them into assassins attire and I don't really use magic that much

Not sure about disenchanting but if there is a default unenchanted robe registered in the game, you can find the ID for that item on the wiki and then type

player.additem <ID> <# of robes you want>
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BREAD FOR THE BREAD GOD! SCONES FOR THE SCONE THRONE!
In the immortal words of Kefka, "Don't make me hate at you"

Get a crafting mod that will allow you to make the Mythic Dawn robes.
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Mr. Spock, the women on your planet are logical. That's the only planet in this galaxy that can make that claim.