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 my new design in a first embodiment; and,
FIG. 2 is a front view of a display screen or portion thereof with graphical user interface showing my new design in a second embodiment.
The outer perimeter illustrated by a pair of broken lines in FIGS. 1 to 2 represents a display screen or portion thereof and forms no part of the claimed design. The remainder of the broken lines illustrating portions of the graphical user interface forms no part of the claimed design.