Gen2 Jimny Oil issue

Hey all. Recently my 92 jimny has been hesitating under high load. Finally got the chance today to take everything apart and try to figure out the issue.

I discovered quite a bit of oil in the intake filter so I took the whole system apart and discovered oil everywhere the valve cover breather hose fitting all the way through to the intake then through the diverter valve to the intercooler and ultimately the throttle body. The metal breather hose elbow coming out of the valve cover was almost totally plugged with sludge/oil. This leads me to have a few questions.

I know some blow by is normal but could the plugged breather hose elbow be the source of all the oil throughout the intake system? Also could that plugged elbow cause the hesitation/misfire I'm getting under high load or should I be looking elsewhere? Could this be a diverter valve problem? I can only seem to source the diverter valve (P/N 18119-72B70) on one website that currently isn't shipping to the US. With that being said is there an alternative for us in the states? Can I just eliminate it all together?

Thanks for your time.

Quick edit that I forgot to mention: I have already changed plugs/distributor cap wires and rotor in an attempt to rectify the break up under load with no success.

Welcome to the forum. By the use of the turbo word I assume you have a Japanese kei version? Yes gunged up breather pipes are not ideal. Unfortunately I don't know enough about the early kei gen2 to offer specific advice but it's quite common to use a catch can in the breather system instead of feeding into the intake on many turbo engines like Subaru and Land Rover tdi and td5.