A Tesla Model Y has a 1700lb battery, and 300 mile range. So as a rough approximation, I could get 70 miles of range with a 400lb battery in place of the 400lb engine. That would be more than enough for me. Realistically, I could probably go even further than 70 miles with that size battery since the Porsche is a much smaller car, that weighs only 60% what a model Y weighs.
I'll probably wait until my Porsche engine (which runs perfect now) has some sort of expensive failure. Rebuilding a porsche engine properly is crazy expensive, more than the parts for an EV conversion.
Here's the thing... if you're going to do all of the work and expense of an EV conversion (maybe $100k for a pro job, or $10-20k in parts plus a lot of work), you want something unique and fun to drive. Nothing is really as fun to drive as a Porsche...