Something is definitely out of alignment. I'd guess this is a problem with RD hanger, but you said that you have already aligned it. Are there any signs of damage on the RD itself, especially around attachment point? What about the jockey wheel cage?
And no, there's no such thing as "cross-chaning" (and hasn't been since 1990s). Every time someone tries to tell you to "stop cross-chaning" they are simply trying to troll you. Your drivetrain is designed with one purpose in mind: to permit you to use big-big combination - the most important objective of all bicycle drivetrain design in the world for the last 30 years. If you can't use big-big with a modern drivetrain, your drivetrain is broken. If you are avoiding use big-big with a modern drivetrain, you are doing it wrong.
It appears that you are using a RD with a fairly large capacity, i.e. with a long jockey wheel cage. So, given your chain length and chainstay length, in the big-big configuration the lower jockey gets pulled far forward (fairly close to the chainring). This results in the lower jockey "feeling" the effects of chain skew, which might be what's causing the problem. I'd guess that if you installed a [slightly] longer chain, the lower jockey would end up being a bit further away from the chainring and the problem would go away. Or, alternatively, if you used an RD with a shorter cage. Having said that, I'd still note that your chain length looks fine to me.
Last edited by AndreyT; 07-26-23 at 04:07 PM.