My 2020 EGT N-Line now runs like an I30 N. No kidding, borderline scary fast.
My solutions:
1. Swap out coilovers. They're a Hyundai-mandated recall for just about every GDI 1.6 Turbo in their lineup. Long story short, they're utter trash. Problem is, the company-based replacements are scarcely better. Get the coilovers I listed above and the majority of your problems with misfires will go away. Roughly $500 shipped.
2. Get Gumout Fuel System Cleaner with Regane (GDI-safe, won't void warranty) and use it every 3K miles or so. I suspect the GDI gunks up the cylinder heads. This fixes that issue. None of the other treatments I've found at twice the price or more -- during a Gumout lack of stock, specifically -- seem to do anything to improve performance and gas mileage.
If you want your car to go really fast (like I demand of my automobiles):
1. Get a plug-in removable turbo tuner from TDI, out of Chelmsford, UK. Five minute install/removal for shop days. No record in ECM, warranty-safe. Roughly $350 shipped.
2. Get Pedal Commander for instantaneous throttle body response. NOTE: Similar items are available at various price ranges; but, I can only comment on the qualities of what I have on the car. Small device, Bluetooth-enabled. I have mine secreted away below the dash and use BT to turn it on/off and to select modes. I just turn it off for shop days; no logs, warranty-safe. Roughly $250 shipped.
In closing, ya gotta get the Hyundai coilovers out of your car. I'm sorry, cuz $500 is a big bite. But, doing the other things without addressing the root cause of misfires is like building a mansion on a garbage dump. Still, for a total of ~ $1,000 you can get a vehicle with in excess of 246 hp and 250 ft. lbs of torque and instantaneous acceleration to all that power. My car 0-60 sub 5 seconds, just letting the DCT handle shifting (non-sport mode) and half-pedal on the throttle. The only time I have to use the flappy paddles is to shift 3 times in 1 second intervals to 7th gear after the pull; never gets above 6K RPM. I've got great tires and they frequently break away on a hard pull, even when already rolling... My car is now the best traffic-beater I've ever owned! And 32.8 MPG, driving like an utter maniac. YMMV.
My settings:
1. TDI Tuner: level 4 (default) out of 7
2. Pedal Commander: Sport, bumped up 2 notches.
Happy Motoring,
-zed
P.S.
DCT shifts fantastic, now; no more hesitations or 'uncertainty' as it auto-shifts.