I have heard that there are treatises on Yoga from Rishis other than Patanjali and one of them is from Rishi Jaimini. Is this true? What are the other Yoga treatises available today and is there any translations of the same?
No, it is not true. Jaimini does not have a work on yoga but on astrology (see for example https://en.m.wikipedia.org/wiki/Jaimini_Sutras). There are many texts on yoga and well known are Shiva Samhita, Hatha Yoga Pradipika for example, regarding Hatha Yoga. Both of them have been translated in english.