The ornamental design for a displayscreen or portion thereof with graphical user interface, as shown and described.
FIG. 1 is a front view of a display screen or portion thereof with graphical user interface, showing our new design according to a first embodiment; and,
FIG. 2 is a front view of a display screen or portion thereof with graphical user interface, showing our new design according to a second embodiment.
The outer perimeter broken lines in the figures depict a display screen or portion thereof and form no part of the claimed design. The remaining broken lines in the figures depict portions of the graphical user interface that form no part of the claimed design.