Can people with mg receive the flu shot?

No absolut contrain. If mg means myasthenia gravís then if the disease is active probable is convenient to wait. There is not an absolut contraindicación to the flu vaccine unless serious allergies to eggs or chichen or previous guillain barré . I would ask the specialist who is treatment your mg if he/she has objecions to it.
Yes. No known issues. If in doubt, call the company that makes the injectable ingredient.