Strength training for Peroneals
I’m no doctor, but they probably dont need to be strengthened. Problems like this usually occur because of lack of proper tissue extensibility, overuse, and excessive force placed on tissue due to altered movement patterns. I would try self myofascial release on the peroneals for a few days and see if that reliefs pain. May be beneficial to also include the lateral gastrocnemius and plantar fascia while you’re down there.
Contact me for strengthening if this does not help.