The Romano_british emergence depends on hard coded triggers and the faction name "romano_british" - I seriously doubt the hard code for that is active in Alex, but you could try, you'd need to internally re-name a faction to find out though.

The spawned_on_revolt faction (ostrogoths) was a horde faction, I suspect it needs to be.

Shadowing ala empire_east and empire_east_rebels might work but that isn't quite the same thing.



Someone else might know more about this - I just know I tried getting a BI mod to run under Alex and first thing it fell over on was not recognising the horde sections in descr_sm_factions.