Being in the work mindset without physically present in the workspace is a challenge that is seen commonly among remote employees.
Boundary theory by Jerry Useem gives an explanation for this phenomenon.
As per boundary theory individuals who wish to shift from home to work mindsets or vice versa, they have to create boundaries that define such spaces. Even within the confines of a home.
Once they cross this boundary, they should be entering a space that is scared to either work/home alone.