Which LH? Any mods? Fuel pressure is pretty easy to test if you have a fuel rail with a schrader valve on it. If not, then you have to connect some adapter inline with the fuel hose to test it. Basically, just hook up a fuel pressure gauge (can be rented from autozone etc) downstream of the fuel pressure regulator and drive it until it acts up and if the pressure is dropping below 40 psi at the same time you are leaning out, check fuel pump, filter and fpr. Fuel pressure sounds like the culprit to me. O2 sensors usually just stay fucked up would cause problems at lower rpm and idle and don’t do intermittent stuff like what your video showed.