Where is the speed sensor?

Trying to replace the output speed sensor on my 2002 Ford focus se zetec automatic transmission. But can’t seem to find where it is.

60 seconds on Google
261618_Noname_43

My understanding is that diagram is for the manual transmission. Because I looked underneath the car in that exact area and could not find it.

Tester

“Output speed sensor” is a little ambiguous. What’s the speed sensor used for? Measuring the crankshaft rpm? The turbo rpm? The transmission output shaft rpm?