Only one can be master. And it is best practise to set the most important recording device as master.
So one micstacy as master, the other slave to that one via WC. Then both via adat to whatever you find nost practical. The digiface or FF as slave to adat, no WC needed.
The only downside is that you will have to switch samplerate from micstacy 1.

Hi Ramses , yes I am good, thanks! You too?
And yes that, AES, is a great idea, especially if sample rate changing is needed. And you don't have the issue that adat always has a 44 or 48k clock.

AES is a digital connection compareable to ADAT, SPDIF, etc ...
There is no sound degradation in any direction (A/D, D/A) as it is digital transfer of audio data.
Steadyclock works with AES as well (with any digital connection).

The advantage, as vinark already mentioned is, that you have 44.1 - 192 kHz ...
So if you have the recording interface as clock master then you can e.g. select 96 kHz in the application,
the ASIO driver sets the interface to 96kHz and the connected units will learn 96 kHz through AES.

If you use ADAT connections for clock distributions, then the connected devices can only distinguish between 44.1/48 kHz.
The "bundling" of multiple adat channels (2/4 for double/quad speed) can't be recognized by the devices for proper clock distribution over 48 kHz.

So using AES for clock distribution you might get rid of this problem ...
But then you should better use an interface which has at least 1 AES port for clock distribution.

For the transfer of audio signals you can use ADAT or MADI.

If it doesn't need to be an USB based solution, then also a RayDAT could be a very good choice.
Has everything you need. 4x ADAT, AES, SPDIF.

Then additionally an ADI-2 Pro FS R BE for monitoring and maybe even an ARC USB and then you have your dream setup.

According to manual the Micstasy has 1 AES input for clock sync (and 4 AES outputs). Can also be used as format converter.
The analog input signal will be send to all digital outputs (ADAT, MADI, AES).

You could also use a recording interface with MADI I/O, which might give you more flexibility in terms of placement of the Micstasies (maybe in different rooms or on stage).

I think excellent would also be the HDSPe MADI FX.
It has 3 MADI  channels, Analog Output (for phones), AES (to connect an ADI-2 Pro for monitoring)
and the only card with FX chip, optimizing driver (less resource consumption) and redundancy features.
See my review here:
https://www.tonstudio-forum.de/blog/ind … Pro-FS-BE/

Also excellent would be UFX+ with MADI, then you have USB/Thunderbolt and DURec for stand-alone and backup recordings to USB Disk, USB Stick, Mobile SSD ... very practical.