Fey crossings (DMG pg. 50) allow visitors to cross from the Material Plane to the Feywild. The description explains that they require key similarities between the corresponding locations on both planes, but doesn’t explicitly say whether the crossing exists on both planes.
The examples given of entering a fey crossing seem to focus on traveling to the Feywild (admittedly, probably the part most players are interested in). But can one return the same way? Can other creatures come through the crossing from the other side?
The description of shadow crossings on the next page suggests that this is true of Shadowfell ("creatures can walk from one plane to the other") but I am not sure whether this should be read as a difference or a similarity.
If this information isn’t specified in 5th edition, support from prior editions would be acceptable.