Valentin began working in commercials. In 2010, she made her first television acting debut through a children's show created by
GMA Network,
Tropang Potchi along with other notable child stars like
Bianca Umali,
Julian Trono and
Ella Cruz. She later made guest appearances to minor roles on various Filipino television shows like
Princess in the Palace (2015),
Meant To Be (2017),
Mulawin vs. Ravena (2017), ''
Super Ma'am (2017), Daig Kayo ng Lola Ko (2018), Sherlock Jr. (2017), Kambal, Karibal (2017–2018), Kapag Nahati ang Puso (2018), TODA One I Love (2019), Dahil Sa Pag-ibig (2019), Magkaagaw (2020), Kaibigan: The Series
(2020), Anak ni Waray vs. Anak ni Biday (2021), Dear Uge (2021), Pepito Manaloto: Ang Unang Kwento (2021), Regal Studio Presents (2022–2023) and Hearts on Ice'' (2023). In the 2020s, she starred as Jo Escobar in
Ang Dalawang Ikaw (2021), Stella Fernandez in
Apoy sa Langit (2022), Beatrice Royales in
Royal Blood (2023) and Hannah Salalac in
Lovers & Liars. She also appeared in classic Filipino films such as
Aswang (2011),
Maledicto (2019) and
Apo Hapon (2024). In 2024, Lianne starred on the Philippine murder mystery drama series ''
Widows' War, reprising her role as Beatrice Royales from Royal Blood''. ==Filmography==