26-year-old Smith made her England debut in 2018 for the ICC Women's T20 World Cup campaign against Bangladesh.
The left-arm orthodox bowler was signed by the Northern Superchargers in The Hundred and most recently played for the Northern Diamonds in England’s One-Day competition – the Rachael Heyhoe Flint Trophy.
Smith said she was looking forward to heading down under and making her WBBL debut.
“I’m excited to join the team in Tasmania later this month and experience everything the Big Bash has to offer,” Smith said.
“I’ve watched the WBBL from the UK and can’t wait to pull on the Stars green this year.”
Making the move from WA, the young gun Darke is ready to play her part in achieving success for the Stars.
“The Stars squad is filled with such experienced players, I’m thrilled to be joining them and am ready to take advantage of the knowledge pool the team has,” Darke said.
“Seeing them get so close last year and knowing what they’re capable of, I’m ready to play my part this season.”
Melbourne Stars WBBL Head Coach Jarrad Loughman welcomed the signing of Smith and Darke.
“Linsey will add another level of versatility to our squad this season with her left arm spin and batting in the middle order. Her experiences on the international stage will be beneficial to our squad, that is diverse in age and experience,” Loughman said.
“She had a terrific English summer, highlighted by a strong tournament at The Hundred. Both she and Maddy Darke will be fantastic additions to the team with the experience to share and opportunities to learn, we’re looking forward to seeing both of them thrive in a new environment.”
Melbourne Stars General Manager Blair Crouch said, “We're thrilled to welcome Linsey and Maddy to the Stars family, both quality players who’ve both proven themselves as integral team members to their respective sides in the past few years."
Current squad: Meg Lanning (c), Elyse Villani, Annabel Sutherland, Lucy Cripps, Nicole Faltum, Tess Flintoff, Kim Garth, Anna Lanning, Georgia Gall, Rhys McKenna, Erin Osborne, Maia Bouchier (ENG), Maddy Darke, Linsey Smith (ENG).