Question: how to evolve eevee into espeon ripple in time?
Answer: If you haven't evolved an Eevee into an Espeon yet, you can name the Eevee “Sakura” to turn it into an Espeon, guaranteed. Otherwise, you have to walk 10 km with Eevee and evolve the buddy Eevee during the day. Keep in mind that the Eevee has to remain your buddy as you evolve it.