I'm posting this around in hopes of an answer. Not for tat, though I could see this as a decent one. I need to study more to be as sure of the Irish grammar as I am of my Russian grammar.

Would this be an appropriate translation of the phrase "Our love is our only legacy":

Is é ár ngrá ár n-oidhreacht aonair!

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I'm a beginner, so corrections and suggestions are much appreciated!
"What? First we give a month to black history, now we're blowing seven days on the Irish!"
Pierce, upon hearing about Green Week

I don’t think that works. For one thing, the double ‘our’ sounds forced and heavy in Irish; and for another, I’d understand ár n-oidhreacht aonair to more likely mean ‘our heritage of solitude’, rather than ‘our only heritage’.

If you want to translate it literally, this would be better:
Is é ár ngrá an t-aon oidhreacht atá againn
‘our love is the only legacy we have’

But I think this would actually flow better:
Is é an grá an t-aon rud a fhágaimid inár ndiaidh
‘love is the only thing we leave behind’

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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.

I was going to make it longer, but that sounds better.

Welcome to the forum Yobar.

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It is recommended that you always wait for three to agree on a translation.
I speak Connemara Irish, and my input will often reflect that.
I will do an mp3 file on request for short translations.
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Thanks, all, for the input!

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I'm a beginner, so corrections and suggestions are much appreciated!
"What? First we give a month to black history, now we're blowing seven days on the Irish!"
Pierce, upon hearing about Green Week