Will Ishgard have a low and medium level camp?

[rina_inverse]

There is no reason to believe there are "local Ishgardian adventurers", as Ishgard is a closed city, seemingly all elezen and very religious. I doubt being an "adventurer" is a real option for many, and those who do would be rebels.

Fair enough

Anyhow lore wise no one HAS levels, so the point is moot.

What about those guard outside any camp and city state? all of them have level. the one in Mor Dhona even call seasoned adventurer, to differentiate from city state military like brass blade or yellow jacket

I very much doubt there will be any low level zone, there is no reason for it. Mid-level maybe, Coerthas is already for the 30s, so if they add another part of Coerthas maybe that will be similar.

well, even Ishgard military would need to train to be able to reach level 50

Pick Ishgard as starting city? No way.
Grand company? I don't see why not, but it would require a lot of reworking of various things (including PVP).

Far future then. though i understand it will make a large overhaul on the game core

[Felis]

but does central coerthas count as the new expansion?

No, but the jobquests of the new jobs don't need to send you to the new zones. Especially with Central Highlands, a lv30+ zone, straight in front of the Ishgard entrance gate. Ever the lv30-50 jobquests of the new jobs send you only through the central highlands, like with DRG, or they send you through whole Eorzea, but not into the lv51+ zones.

What about those guard outside any camp and city state? all of them have level. the one in Mor Dhona even call seasoned adventurer, to differentiate from city state military like brass blade or yellow jacket

That level count as game wise, not lore wise.

Because no Ishgardians could possibly go outside to Central Coerthas. This is flawed logic given the game environment that already exists would suffice for the Ishgardian soldiers/adventurers. In 1.0 days almost the entire zone was filled with monsters that could one-shot you, so given the original lore the new Ishgardians have it pretty easy by comparison.

Not in the area that got used the most time. From Camp Dragonhead to Dzemael or Camp Glory was nothing that was dangerous. Only in secluded corners, away from the main ways.