If your goal is to lose weight, I’ve read that the last couple hours of your fast is a good time to exercise since your body is in ketosis and will burn more fat for energy. That’s what I’ve been doing for the last month and a bit. I don’t find it affects performance all that much but there are some days where I just don’t have the energy for a heavy workout. I still workout but I just go easy. I fast for 16-18 hours at a time and a similar eating window as you. I go to the gym around 9/10am.
There are also a lot of recommendations out there that say you shouldn’t work out on an empty stomach. Just go with what works for your lifestyle. I prefer a morning workout as I find it helps get over the bump of those last few hours of my fast and an afternoon or evening workout just isn’t ideal for me.