Their dress was quite distinctive, so existing ECW models generally won't do.
It's an interesting army because, although weak in Horse, it can function as a hybrid Pike-and-Shot/irregular army, with a potential to have very large numbers of traditional Irish fighting in loose order or skirmishing as "kerns," and may also have a healthy contingent of the fiercesome "Antrim Redshanks."
The line was sculpted, and painted for display, by my Irish Catholic confederate, "clibinarium."

Here's a preview of an infantry unit based for FoGR:

And the individual codes --
Confederate Irish pikemen:

Confederate Irish heavy musketeers:

Confederate Irish light musketeers/calivermen:

Confederate Irish pike and shot unit command (flag not included):

Confederate Irish with traditional weapons:

Redshanks/Highlanders mostly with warbow:

Redshanks/Highlanders mostly with musket:

Being cast now are:
1) Irish pistolier horse (mostly Anglo-Irish so in more typical European horseman's dress, but still rather badly equipped)
2) Irish high command mounted (commander in european garb, for Ormonde, etc, plus standard and muscian)
3) Irish high command mounted (commander in traditional Irish dress, for O'Neill, etc, plus standard and musician)
4) Dragoon nag and dismounted horseholder (one per base to make infantry with muskets Dragoons)
Next step will be to convert the Irish to serve with Montrose, adding broadswords and a few bonnets. Also some typical Scots pike and shot, and some Scottish type horse will be made, as these made up the bulk of Montrose's force. This expansion will of course permit the construction of Covenenting armies as well. We may even make a McColla model too, although players might prefer to simply use a 28mm Highlander for that.

The first batch is coming in the next few weeks! The Confederate Irish mounted in perhaps a month and a half or two. Stay tuned.