Interaction between Teferi Time Raveler and Enduring Ideal
No, it doesn't stop it. Teferi says:


  Each opponent can cast spells only any time they could cast a sorcery.


(emphasis mine)

But copying a spell is different from casting it:


  706.10. To copy a spell, activated ability, or triggered ability means to put a copy of it onto the stack; a copy of a spell isn’t cast and a copy of an activated ability isn’t activated.


Therefore, Teferi doesn't affect the Epic ability.