fé choinne does it mean for?

Yes. Faoi/fá/fé choinne means ‘for/in order to/for the purpose of’.

(Fé is just the Munster (?) version of the preposition faoi; fá is the Ulster form)

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Not a native speaker.

Always wait for at least three people to agree on a translation, especially if it’s for something permanent.

My translations are usually GU (Ulster Irish), unless CO (Standard Orthography) is requested.

yes "fé" is Munster only.
Munster fé choinne
Connachta faoi choinne
Ulster fá choinne

Fá choinne is very common in Donegal ; in the other dialects there are other ways to say "in order to", like "le" or "chu(i)n" or "d'fhonn", etc

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Is fearr Gaeilg na Gaeltaċta ná Gaeilg ar biṫ eile
Agus is í Gaeilg Ġaoṫ Doḃair is binne

which is preferable fé choinne or i gcomhair? or maybe le haghaidh?

I've been studying the southern dialect, what's the best way to translate word "for"?

It depends partly on the sentence, and partly on dialect. In Ulster, for example, I haven’t heard i gcomhair (or fá chomhair, for that matter) used very much. Fá choinne is much, much more common. But I’m sure there are other dialects where i gcomhair/faoi chomhair is more commonly used.

Le haghaidh means something slightly different from fá choinne, but it’s very hard to pinpoint how. In many cases, they’re completely synonymous, but in some cases, I think there’s more of a focus on how exactly something is to be used with le haghaidh, while fá choinne deals more with purpose something will have. But it’s quite vague, and in most cases, you can probably substitute one for the other with no change in meaning whatsoever.

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Not a native speaker.

Always wait for at least three people to agree on a translation, especially if it’s for something permanent.

My translations are usually GU (Ulster Irish), unless CO (Standard Orthography) is requested.

Well I'd say "i gcomhair" is much used in Munster, "le haghaidh" in Connachta and "fá choinne" in Ulster - to make it short.

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Is fearr Gaeilg na Gaeltaċta ná Gaeilg ar biṫ eile
Agus is í Gaeilg Ġaoṫ Doḃair is binne

go raibh maith agaibh!

When I use "fá choinne" it is followed by a noun or noun thought. (Thug mé bróntannas fá choinne an bhreitlá.) I brought a gift for (for the purpose of) the birthday.

When I use "chun" or "le" it is followed by a verb or verbal thought. ( Chuaigh mé go dti an bhialann chun (or 'le') lón a ithe.) I went to the restaurant (for the purpose ) to eat lunch.

I may or may not be using these correctly, but that's how it's evolved in my head and speech. My Irish has an Ulster twist to it and people understand me and nod when I say such things.

Ag obair liom (Working away)
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