I'm trying to say, "The colors of the flag of the Republic of Ireland are orange, green and white"
I know there a few different ways to say this. Which of the following are correct:

Is dathanna bhratach Phoblacht na hÉireann oráiste, glas agus bán
Dathanna bhratach Phoblacht na hÉireann is ea oráiste, glas agus bán
Oráiste, glas agus bán is ea dathanna bhratach Phoblacht na hÉirenn

Thanks in advance. I would also appreciate any alternate suggestions.

Both wrong because dathanna [...] na hÉireann is a definite noun phrase.
So a pronoun iad is necessary: Is iad dathanna [...] na hÉireann ...
And ea can’t be used.
Both sentences make dathanna ... the predicate. But it is subject.



I don't know how to use colours here, I'd add na trí dhath

Is iad na trí dhath, uaine agus bán agus flannbhuí, dathanna bhratach (Phoblacht) na hÉireann.

Oh yeah, forgot that the presence of the genitive makes the entire phrase definite.




Is it preferable to use uaine instead of green and flannbhuí instead of oráiste when describing the colors of the Irish flag?

Because it is so called in Bunreacht na hÉireann: ("An bhratach trí dhath .i. uaine, bán, agus flannbhuí, an suaitheantas náisiúnta.", Art. 7)
And "uaine" because it is an artificial green.

God forbid they use the word "oráiste".