The POSH policy covers women employees as well as visitors.
it also covers harassment of women employees and visitors from outsiders and visitors within the premises.
When WFH is implemented, while the possibility of physical harassment is eliminated, the possibility of oral harassment and visual malpractices are still prevalent, including through communication on WhatsApp, email and other methods.
Therefore, it is unprofessional to say that WFH stops sexual harassment automatically. You need to have a POSH policy and it should be modified to include the WFH and all possible scenarios in which sexual harassment can still happen online.