The holders, Cliftonville, are set to face rivals Glentoran in this year's Women's Challenge Cup final at Windsor Park.
At Dixon Park, the hosts took an early lead against Crusaders when Caitlin McGuinness fired home after just five minutes.
Her sister Kirsty doubled their advantage before Louise McDaniel slotted home Cliftonville's third just before the break.
The side progressed to their fourth successive decider following a comprehensive performance that saw them dominate from start to finish.
In contrast, the match at Solitude was described as much tighter by observers who noted the difficulty Glentoran faced in breaking the deadlock.
It took until the 81st minute for Glentoran to secure their advancement when Gracie Conway headed home Emma McMaster's cross against Lisburn Ladies.
The Reds are aiming to secure a third successive Challenge Cup after beating Linfield in last year's showpiece at Windsor Park.
While the Reds may have won the past two Challenge Cups, the Glens hold the record for the most wins with 11 titles.