I'm sure there are many reasons not to use the 2 liter bottle for this
purpose, and many better alternatives. I'll thank everyone in advance
for telling me those facts, but, will a 2 liter plastic soda bottle
hold the beer or wine without exploding? Say if the fermentation was
not complete or if it restarted?

I've seen 2 liter bottles pressurized to failure (not pressure gauge
used) and they seem pretty strong. However I have no idea of the
strength needed, nor any idea of what a fermenting beverage could
generate.

Thanks

Eric