I couldn’t find any S&V measurements for the Yamaha A1000 series, but found a A2000 series and Denon X4000 series.
Yamaha 2070:
191W x 2Ch 8 ohms
259W x 2Ch 4 ohms
118W x 5Ch 8 ohms
45W x 7Ch 8 ohms
https://www.soundandvision.com/content/yamaha-aventage-rx-a2070-av-receiver-review-test-bench
Denon X4200:
149W x 2Ch 8 ohms
239W x 2Ch 4 ohms
118W x 5Ch 8 ohms
91W x 7Ch 8 ohms
https://www.soundandvision.com/content/denon-avr-x4200w-av-receiver-review-test-bench
The Yamaha A2000 series has a little more power than the X4000 series for 2Ch, but the same power for 5Ch and a only half the power for 7Ch.
As mentioned, in Direct mode, they will sound extremely similar.
Also as mentioned, the salient difference will be the EQ.
The Denon X4000 series has the same Audyssey XT32 as found in the $7,500 Denon AVP-A1HDCI and $7,000 McIntosh MX122 Pre-pros.
https://www.listenup.com/shop/mcintosh-mx122.html
Yamaha has their own EQ software.
Personally, the salient difference to me is the Audyssey Dynamic EQ (DEQ), which primarily boosts the mid-bass and slightly boost the treble to create what I think is a more Dynamic and Lively larger-than-life Sound.