I listened to an interview recently, I believe on BBC, where the interviewee said the biggest issue with peace talks is that the international community isn't able to trust Putin to keep his word on whatever is agreed upon. I hadn't considered that, but it makes a lot of sense and I'm not sure how that could change
You draw new borders and stop shooting, that's a start. You then keep the agreement by having enough military for a new invasion to be undesirable. Simple game theory. Trust and promises only work for societies that mutually respect each other.
The same argument can be used in favor of Russia. NATO has invaded plenty of countries under false pretenses in the past. Both Russia and NATO do not have a reputation for keeping their promises.
It is more like saying the axis is known to invade nations because its member states invade nations. Okay, sure, Germany and Italy invaded the soviet union but Japan didn't, you can't say they're not a defensive alliance /s