Ok, gotcha‘... so I just set the SW volume to 12 o‘clock, the crossover to the highest setting, just like in the manuel, and let audyssey do its magic....The setting you pictured is NOT a crossover, it's an LPF (low pass filter) only for the LFE channel.
The subwoofer plays LFE and ALSO redirected bass from speakers set to "small" below the crossover. The crossover on the SPEAKERS determines what gets redirected to the subwoofer, the LFE LPF only filters the .1 LFE channel.
All that said, I don't know what you mean by "manage" your subwoofer. You still need bass management right? The processor (AVR) is going to control that, then once you send the bass managed signal to the subwoofer you can do with it what you will. If you set controls on the sub they will interact with the AVR controls.
For example, let's say you cross your speakers at 100Hz in the Denon AVR. That will apply a 100Hz HPF to the speakers, and a 100Hz LPF to the bass managed signal sent to the subwoofer. But if you set the filter knob on the subwoofer itself to 80Hz, now you're going to be missing content in between 80 and 100Hz. Even if both filters are set to 80Hz, the double LPF on the subwoofer will cause it to roll off more steeply than intended and could create a "suckout" at 80Hz.
Do you have measurement gear so you can actually see what's happening and make informed decisions about this? If not, then you should just let the AVR do its thing.