Current research hasn’t proven that exercise time of day affects metabolism, so exercise when it fits into your schedule 30 minutes, 5 times per week. Just exercise!
Exercising within a few hours of sleep may delay your falling asleep. If sleeplessness happens consider timing your exercise to earlier in the day.
Exercise and a larger muscle mass increase metabolism. With exercise, especially weight training, your weight may not change and may even go up, but you should lose inches overall unless you are into bodybuilding then you will gain inches. In fact, exercise increases metabolism up to 15 hours afterward.