Loss Of Power - 2016 Skoda Rapid Spaceback 1.6 TDI 115

Hi everyone, looking for some advice.

I've got a 2016 Skoda Rapid Spaceback 1.6 TDI 115hp (CXMA), 5-speed manual, with around 125k miles.

I've been experiencing progressive power loss. 1st and 2nd gear feel reasonably good, but as soon as I get into 3rd, 4th and 5th, the power just drops off. It struggles to accelerate, especially uphill. I also get juddering when accelerating in 3rd at around 1,500 RPM. Power loss and juddering gets worse the longer I drive. I've been to a few mechanics, but keep getting different suggestions: charge cooler, DPF, EGR, injectors and turbo actuator. Some are even pointing to clutch and flywheel. I've changed the fuel filter and used EGR cleaner, which improved things noticeably, but the problem hasn't completely gone. No warning lights, and the engine doesn't noticeably run rough.

Has anyone experienced anything similar with the 1.6 TDI? Just trying to narrow it down rather than keep replacing parts without knowing the actual cause. Or maybe scrap it at the end for an Octavia.

Another thing to mention, no issue with clutch slippage its like there is resistance holding the car back and thus more heavy on the fuel consumption. Mechanical have suggested just to keep driving untill it breaks down.

Any advice would be appreciated. Thanks!