The Dravanian Hinterlands and The Lochs R the most efficient expansion areas 4 Yokai

[Tranquilmelody7]

There's no item level sync for fates, only a level sync.
If you have choice of fates to grind, you always want to opt for fates that will sync above the respective level cap for the expansion so you can reap benefits of massive stats to quickly defeat your fated foes.

All the Hinterlands and Lochs fates will sync you above 60 and 70, making them ideal places to grind for Yokai loot.
The Hinterlands also has the added benefit of being a relatively compact area, nulling the need for an Aetherytes.

I see some people doing fates in the Forelands, Churning Mists and the Azim Steppe and they are just terribly inefficient to grind compared to the Hinterlands and Lochs.

I guess I can kind of understand why people flock to the Azim Steppe though to be fair, as it has 3 well placed Aetherytes and is pretty surreal zone in general.

[Derio]

Simply due to the amount of inclusion as well. There are still people leveling up and going through content, not to mention some people are using this to level jobs as well, if they dont have that job at level cap then it wont be the most ideal place for them to farm. With the sheer amount of players, regardless of zone fates are being done in a fairly quick manner so really any location is a good location as long as the population is there.

[Ultimatecalibur]

I see some people doing fates in the Forelands, Churning Mists and the Azim Steppe and they are just terribly inefficient to grind compared to the Hinterlands and Lochs.

Forelands is the domain of the Coeurlregina World Boss FATEs. The Churning Mists has a rare World Boss FATE that requires completion of both a FATE chain and 3 other FATEs. Some players may be using this event as an opportunity to check both of those achievements off.

Azim Steppe isn't bad because it is an open mostly flat zone with 43 FATEs in it with 13 of those in one FATE chain. The Lochs has 34+Ixion but very mountainous terrain. FATEs melt quick enough even without out leveling the zone while it is much faster to get around the zone.

[Fynlar]

These places are where I went personally to do my FATEs (for the same reason suggested by this thread), and I got it done (for the four new weapons) in about 3 hours.

That being said, I'm sure you can get it done nearly as quickly nearly anywhere else if those zones have healthy trains going. I just wouldn't suggest Azys Lla due to the lack of groundspace and the significant distance between said groundspaces.

If you were to be in the situation of soloing FATEs though, I'm pretty sure a 60/70 level cap zone (except Azys Lla) will work better than a synced one; there's a significant difference in killing speed when you've got item levels backing you up.

[Tranquilmelody7]

Simply due to the amount of inclusion as well. There are still people leveling up and going through content, not to mention some people are using this to level jobs as well, if they dont have that job at level cap then it wont be the most ideal place for them to farm. With the sheer amount of players, regardless of zone fates are being done in a fairly quick manner so really any location is a good location as long as the population is there.

True, I admittedly exaggerated when I was saying they were terribly inefficient.
As long as you're having fun and zones are bustling, any area will suffice.

I just want to offer advice and state that the Hinterlands is definitely optimal for HW for those who wish to maximize efficiency.

The fates in the Lochs will definitely melt the fastest in SB, but I suppose it's debatable if it's more efficient overall than the Steppe due to the relative ease of traversal for the latter compared to the former.