I’ve never used a torque wrench when installing spark plugs.
This is because on some applications, you can’t get a straight access to the spark plugs. And if you’re using a swivel joint to gain access to the spark plugs, a torque wrench is useless.
I use the old tried and true method when tightening spark plugs.
If the spark plug has a tapered seat, I tighten the spark plug until it seats, and then tighten it 1/16 of a turn.
If the spark plug has a gasket seat, I tighten the spark plug until it seats, and then tighten the spark plug 1/2-3/4 of a turn.
Tester