Thanks to chatgpt here is a list of airlines that fly between Toronto and Dub

Air Canada: Canada's largest airline, offering direct flightst from Dublin to Toronto Pearson International Airport (YYZ).

Aer Lingus: Ireland's flag carrier, with flights to Toronto Pearson International Airport (YYZ).

British Airways: British Airways offers flights from Dublin to Toronto Pearson International Airport (YYZ) with layovers in London.

Lufthansa: Lufthansa, the German airline, provides flights from Dublin to Toronto Pearson International Airport (YYZ) with layovers in Frankfurt or Munich.

KLM Royal Dutch Airlines: KLM offers flights from Dublin to Toronto Pearson International Airport (YYZ) with layovers in Amsterdam.

Air France: Air France operates flights from Dublin to Toronto Pearson International Airport (YYZ) with layovers in Paris.

Delta Air Lines: Delta provides flights from Dublin to Toronto Pearson International Airport (YYZ) with layovers in the United States, often in cities like New York or Atlanta.

United Airlines: United Airlines offers flights from Dublin to Toronto Pearson International Airport (YYZ) with layovers in the United States, often in cities like Newark or Chicago.

American Airlines: American Airlines operates flights from Dublin to Toronto Pearson International Airport (YYZ) with layovers in the United States, often in cities like Philadelphia or Chicago.

WestJet: WestJet, a Canadian airline, provides flights from Dublin to Toronto Pearson International Airport (YYZ).