Xenoblade 2 took about 3.5 years to make

[Nuvendil]

caffeinade said:

Nuvendil said:

I can't be positive but comparing X to the original I think the X engine is built on the original engine.  There's just some very odd quirks that engine had that stuck around.  The most obvious is the grass solution being identical.  I doubt they repeated that in a new engine.  So porting the original to the X engine should be a pretty smooth transition.  Not sure they could or would eliminate loading between regions, I think that's more a structural issue.

Perhaps.
But in the same way CoD: WWII is built on id Tech 3, or Titanfall 2 is built on Source.
Both games use Heavily modified engines, that only vaguely resemble their parents.

XBC2 is pretty much just built on XBCX's engine.

True.  But worth pointing out, XC2 features a number of improvements and notable changes to the X engine.  It's not just a new game on the same engine.