Are shards different?

[Kranel_San]

This may sound like a strange question, but I had the thought after thinking about why the first and the source are different despite being the same world and the same landmass. I'm aware that this is answered in-game indirectly.
The reason why they're different in civilizations, knowledge, structures, perceptions, names, and other things is because of the calamities and any external interventions.
But let's say for example that there are two shards untouched by the ascians and mostly by any external interventions excluding Hydaelyn herself. Would they be different? Would people make different decisions and have different names? Would the two shards be different or very identical?