You would not be liable for taxes in Ireland for RSU shares that vested while a US resident.
Here's more detailed info from Irish Tax Revenue.
For more info on how the US handles this, see RSU's and Taxes.
If you vested/sold on the same day, you may get a 1099-B to report the sale, and should end up with a small gain/loss when entering in TurboTax.
@Julian95
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