The 20-year-old makes the temporary switch from the Barclays Women's Super League side having joined them in January.
Femke's professional career started with VV Alkmaar in 2021, before they would go on to become AZ Alkmaar. She made over 50 appearances during her time in the Eredivisie Vrouwen.
On the international stage, the goalkeeper has impressed at youth level for the Netherlands, notably winning the golden glove at the FIFA Under-20s Women's World Cup last summer. She also received a call up to the senior squad in October.
On joining the Magpies, Femke said: "I'm really excited and can't wait to join this amazing club.
"The ambitions and the first impression of the club have been great. I have the feeling that I can develop here well as a player and a person."
Manager Becky Langley said: "Femke is one of the brightest prospects in European football. She has experienced playing in the Eredivisie Vrouwen and understands what it takes to win from her time so far at Chelsea.
"She has the ability to play out from the back and adds further strength to our goalkeeping department."
This signing is subject to FA clearance.