Is it impossible for Sarada to get an Eternal Mangekyou Sharingan?
It is definitely not ideal to give Sarada Sasuke's eyes for an Eternal Mangekyou Sharingan while he's alive. It is possible that she gains it while Sasuke is about to die (kind of like how Kakashi got the Sharingan from Obito). Another way would be to have a genetic clone (which would satisfy the condition of close blood ties) awaken a Mangekyou Sharingan and transplant it to Sarada. (Although the latter is highly improbable)