2 power meters in row , how reduce valu 2 from value 1?

I have 2 power meters after each other, one in the wall socket and then one in a power strip (or what the name is) and now I would calculate so the power meter shows right info, so is it possible to reduce the valu from power meter 2 from the value in power meter 1.

So, “power meter 1 - power meter 2=“

How can I do this?

use a template sensor

to be honest, I had a look at the template, but I couldn’t figure out what and how to do it :frowning: