It is the second new mid-season women’s competition to be introduced by Fifa in recent years.
The inaugural Champions Cup – featuring continental champions from around the world, including Arsenal – will take place next week in London, between 28 January and 1 February.
WSL officials say the planned Club World Cup would result in up to five WSL match weeks being rescheduled, leading to a potential fixture backlog and an impact on player fitness.
They say they have written to Fifa with their concerns and will meet with global officials in London during the Champions Cup to discuss the issue.
BBC Sport has been told the WSL would rather the tournament is played in the summer during a fallow year with no other major global competitions, rather than disrupting the domestic schedule.
The BBC also understands the planned schedule was presented at a WSL meeting with club captains on Monday, with players “shocked” by how busy the calendar could get.
The fact that the Club World Cup is scheduled for between the 2027 Women’s World Cup and the 2028 Summer Olympics is also a concern.
“There are no gaps,” a WSL spokesperson said. “If the tournament is in a different time zone, with the rest and recovery needed, it could lead to rearrangement of a lot of fixtures.
“We know Arsenal will participate and Chelsea are likely to participate as well. It would be great for our clubs but their fixtures would probably have to move to midweek slots which are less attractive to fans. It is delicate timing.”
The WSL is now considering its options, although asking English teams to boycott the competition is not currently on the table.
One option being considered is moving the WSL winter break – which usually takes place over Christmas and New Year – so it covers the Club World Cup in the 2027-28 season.
