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I didn't know exactly where to post this so feel free to let me know if there's a better spot!

So I have a 2009 Honda Civic Hybrid, it has 230k miles on it. I got it two years ago, in pretty not maintained condition, so I've been plucking away at fixing it.
Recently it came up with a fuel system being too lean code, and an EGR leak code. This was after the car started shuddering one day and flashing the engine light (to which after I turned it off for a few minutes and turned it back on, it's never done that again). It also has misfire codes in all cylinders and a random misfire, but the main misfires are in cylinder 1 and 4 (the spark plugs were just done, they're fine. And I've been changing out all the coil packs, I've changed three out of eight of those so far).
I changed the MAP sensor when the fuel system came up too lean, and after I did was when it threw me the EGR leak code. So I changed the entire EGR valve, and checked the hoses in the process. And overall, that helped a lot, though there seems to still be misfiring and the fuel system is too lean. I'm starting to think the cat may be clogged... the original engine light a year ago was complaining about the cat.
But that's not really what I'm concerned about now, although if you have any ideas about that feel free to let me know lol.
About a year ago the car started doing a weird thing where it would turn on the emergency brake light randomly, then immediately after it would turn on the VSA, brake system light, and the triangle "something is wrong, I dunno what" light. Once you turn the car off, it would go away for months, and rarely ever pop up. Initially, I thought maybe it was one of the calipers, I had just changed a few out when it started doing that.
Well like I said, it started doing that a year ago but rarely ever did it. After I changed the EGR valve, that was no longer the case. When I accelerate, it triggers the emergency brake light, and soon after all the lights I just mentioned. The emergency brake light will turn on and off while driving; it turns on when I accelerate, turns off when I brake or let go of the gas pedal.
The main issue with this is that because the car is thinking there's something wrong (despite it braking and steering fine), the hybrid system is virtually just giving up while driving. I have horrible acceleration now, the hybrid battery keeps dying and hardly recharging, it refuses to auto stop...
But why is it doing that? The VSA light isn't even connected to the brakes, it's the steering sensor. There's no symptoms of a bad steering sensor. The brakes are braking fine, I know I have a few brake pads to change but there's nothing critical in the brakes. It's fine on brake fluid and doesn't leak it... and why would it do all this after the EGR valve gets replaced?