In our network we have only ENDC + NSA.
But as far as I know ESS can be deployed with 10, 15 or 20 Mhz With DSS (ESS is of Static, Dynamic or Instant SS).
Mid band starts from 1 to 7.1Ghz where lowest freq can be mid 1 and highest can be mid 2 freq like existing and new freqs in mid band.
Example 1 to 2.6 Ghz existing mid band and 3.5 to 7.1 Ghz is the new mid band freqs.
ESS can be deployed in many scenarios. Below are the one which I am aware of, specially ESS FDD deployment.
ESS can be deployed somewhere between 1 to 2.6 Ghz mid band and we can have CA for 5G with existing 3.5 Ghz NSA (Note: no CA support for mid band presently, r16 may have this feature)
By using a band below sub 1 Ghz like L700 L900 can deploy ESS and CA is possible with existing 5G network NSA like 2Ghz, 3.5 Ghz mid band etc
ESS deployment is to improve the existing 5G coverage.
On top of this you can add F2 freq which increases the 5G capacity based on the spectrum availability.
CA for 5G can be any band which is deployed in your network Starting from 1 Ghz to high band freqs.
One more important thing is that for ESS LTE + NR, we must have another LTE anchoring leg for ESS NR (ENDC).
Hope this will be usefull.
Its just like an overview of ESS.
Additional information or suggestions on this from anyone… Appreciated