Adding a 2nd inverter... options

I have a 3ph 20kw inverter and now have both of the MPPTs working, so it's 'full' from an MPPT perspective.
I now intend to add c. 8kwp to the shed and will put this back to the house/main board via an AC link so will need some sort of inverter in the shed.
I'm pretty sure the 3ph inverter will just detect the extra AC input via the CT clamp and will likely count it OK - hopefully managing the overall export limit (!?)
Would there be a benefit in getting another GE inverter - would the system recognise it better and play nicely? Would it work seamlessly in the app/portal?

Thanks for any thoughts.

Cheers
Ian

Another question/thought...
The 3 phase inverter needs to balance the loads out to the grid I believe...would it be able to cope with say a 6kw load coming down one phase? Given my export limit is 11kw that might be a problem?

[unknown]

Isn't that 11kW per phase export limit?

Or are you on G98 with 3.68kW per phase giving 11.04kW on total?

The latter, 11.04kw limit...I'm not sure it has to be equal across the phases, but I guess that's part of my question

We did apply for full 20kw limit but were restricted to the 11.04kw