If the Regional Bird is a Flying/Electric pokemon or evolves into a Flying/Electric pokemon, than they will skip the Regional Bird, since Ash will never get another Electric type besides Pikachu.
The writers already switched things up on us for Ash's regional bird in Kalos on making it evolve from Normal/Flying into Fire/Flying which is unique among Ash's birds so if they are willing to do this then there is nothing that can really stop the writers from giving Ash a bird that becomes Electric/Flying. Heck the writers had Ash bond with other Electric-types so its possible that Ash could get an Electric/Flying-type that is not a legendary; same for a regional Ice/Flying bird [Delibird doesn't count as it cant evolve and its a Gen 2 pokemon]. It's be cool for Ash to get either an Electric/Flying-type or an Ice/Flying-type regional bird that is able to naturally evolve.
And as said in the 2nd Pokemon movie..."Disturb not the harmony of Fire, Ice and Lightning...", so its possible that the writers could maybe use that as something to go on for birds for Ash in regions.
So far aside from..
Moltres, Ho-oh, and Charizard for Fire/Flying
Zapdos, Thundurus, Fan Rotom, Emolga for Electric/Flying
Articuno & Delibird for Ice/Flying
Talonflame is Ash's 1st Fire/Flying bird.
an Electric/Flying region bird or an Ice/Flying region bird that is able to evolve for Ash is very possible.