Easson said: “Disappointing to lose someone like Hollie. She is a different type of player, we have been watching her a lot at Bristol and she performed brilliantly against Wales in her first cap.
“She really does bring a dominance and physicality. If the World Cup had been three or four weeks later, she would have been alright.”
However, Easson said back-row Jade Konkel, wing Francesca McGhie and second row Sarah Bonar would be fit for the World Cup despite missing out again against Ireland.
Ramsay staked her claim when making her debut as a replacement in last week’s defeat by Italy.
Now the 21-year-old will form a fresh half-back partnership with scrum-half Caity Mattinson against Ireland in Cork in two of several changes to the starting line-up that played in Viadana.
Chloe Rollie comes in at full-back, while Lucia Scott moves from full-back to wing.
In the pack, Anne Young and Alex Stewart are selected at loosehead prop and openside flanker respectively, with Rachel McLachlan switching to blindside and captain Rachel Malcolm moving into the second row.
On the bench, centre Beth Blacklock is poised for a first Test cap since the 2023 Six Nations.
The game at Virgin Media Park in Cork is Scotland’s last Test before the Rugby World Cup gets under way later in the month, with Scotland’s opening Pool B fixture coming against Wales in Salford on Saturday, 23 August.
“Last week was all about performance,” Easson added. “We wanted to see where we had come during pre-season.
“We had a lot of conditioning work, a lot of rugby work and a few system changes with a new attack coach coming in late, a new forward coach as well.
“This week it is around what we do in the game. We’ve got structures and systems in place to win this game whilst one eye ahead looking at Wales, but this is Scotland v Ireland.”