There is nothing published on earthquakes and weather in the UK except in actual historical descriptions, and none of that is on the web. I'm working from recollections of material that I studied many years ago.

Whatever ground connections there are with lightning, I doubt that they extend the 12 km underground that would be necessary in the UK, or the 30+ km that might be required in Taiwan to have any interaction with earthquake sources.

I once had an interesting experience watching a distant thundercloud discharging lightning. It went through three phases: (i) bolts from the top of the cloud to the bottom of the cloud; (ii) bolts from the bottom of the cloud to the ground; (iii) bolts from the bottom of the cloud to the top of the cloud. I've never seen this described anywhere.