Before I discuss potential causes, I would like to first say that the fat gain/muscle loss could very well just be in your head. When we are moving big weights, we tend to see ourselves as very muscular, and of course, the opposite is true as well. I can see from your post that you introduced a large meal pre workout and added a good amount of carbs. This could easily account for water weight. Most of the weight we lose first and gain back is simply water weight. I would caution you to quickly diagnose yourself with gaining fat.
Performance issues may be mental but in a different way. CNS burnout is a myth, but mental burnout is very real. We can go for a very long time with great improvements and then suddenly hit a wall. Instead of continuing on a smart path, we simply bash our heads against the wall thinking our skulls are tougher than the bricks. That is simply not the way to go about this. If this is the case, it would be best to take a week off. Do some yoga, maybe some like cardio, come in just one or two days and move an extremely light barbell around to stay with it, but go find a hobby for seven days to mentally reset.
Bringing us to your workout.
You are doing six movements a day, not a whole lot and not concerning, but I would caution you to change your approach with them. The dip/pullup superset is very metabolically taxing the way you perform them; again, not too concerning, but the rest of your workout builds around this. The other five movements are taken to failure twice in a very short amount of time. Training to failure is NOT the best way to stimulate strength and growth. It has it’s place, but you should almost always leave some left in the tank. When you do use failure, you could keep them for arms and abs as they are smaller muscles and less stimulating to the CNS.
Training with this approach in a deficit, no matter how large or small, is going to be very challenging and can lead you past overreaching. In order to remedy this, I would recommend you take a week off as described above, reset your training- possibly picking up a Thibaudeau template as it seems that is more your style - and let the results come to you.
Remember, as we get further into lifting, the more important it become to train smarter not harder.