The 27-year-old shot-stopper joins the club on a permanent deal from Bristol City, where she spent the second half of last season competing in the Women’s Super League.
Before her six-month stint with the Robins, Yañez represented National Women’s Soccer League outfit San Diego Wave.
It is not the Macon-born goalkeeper’s first spell in English football, however, as she previously spent three seasons with London City Lionesses, keeping a club-record 24 clean sheets in 72 appearances and helping them finish Women’s Championship runners-up in 2021/22.
Yañez also had another spell in the NWSL with Washington Spirit, where she began her professional career, and becomes Crystal Palace’s second arrival of the summer after defender Katrine Veje.