Display screen or portion thereof with transitional graphical user interface

FIG. 1 is a front view of a first image in a sequence for a display screen or portion thereof with transitional graphical user interface, showing our new design;

FIG. 2 is a front view of a second image thereof;

FIG. 3 is a front view of a third image thereof;

FIG. 4 is a front view of a fourth image thereof;

FIG. 5 is a front view of a fifth image thereof;

FIG. 6 is a front view of the display screen or portion thereof with transitional graphical user interface of FIG. 1 , shown in the context of a device;

FIG. 7 is a front view of a second image thereof;

FIG. 8 is a front view of a third image thereof;

FIG. 9 is a front view of a fourth image thereof; and,

FIG. 10 is a front view of a fifth image thereof.

The appearance of the transitional image sequentially transitions between the images shown in FIGS. 1 through 5 and FIGS. 6 through 10 . The subject matter of this patent includes a process or period in which an image changes into another image. This process or period forms no part of the claimed design. The broken line showings of the display screen in the Figures and the device in FIGS. 6-10 are included for the purpose of illustrating environmental structure and form no part of the claimed design.

The broken line showings of the letters in FIGS. 2 , 3 , 4 , 5 , 7 , 8 , 9 , and 10 are included for the purpose of illustrating portions of the display screen or portion thereof with transitional graphical user interface and form no part of the claimed design.