Display screen or portion thereof with transitional graphical user interface

FIG. 1 is a front view of the first image in a sequence for a display screen or portion thereof with transitional graphical user interface showing my new design according to a first embodiment;

FIG. 2 is the second image thereof;

FIG. 3 is the third image thereof;

FIG. 4 is the fourth image thereof;

FIG. 5 is the fifth image thereof.

FIG. 6 is the sixth image thereof;

FIG. 7 is the seventh image thereof;

FIG. 8 is the eighth image thereof;

FIG. 9 is the ninth image thereof.

FIG. 10 is the tenth image thereof;

FIG. 11 is the eleventh image thereof;

FIG. 12 is the twelfth image thereof;

FIG. 13 is the thirteenth image thereof;

FIG. 14 is enlarged view of the claimed portion of FIG. 1 , shown separately for clarity of illustration;

FIG. 15 is enlarged view of the claimed portion of FIG. 2 , shown separately for clarity of illustration;

FIG. 16 is enlarged view of the claimed portion of FIG. 3 , shown separately for clarity of illustration;

FIG. 17 is enlarged view of the claimed portion of FIG. 4 , shown separately for clarity of illustration;

FIG. 18 is enlarged view of the claimed portion of FIG. 5 , shown separately for clarity of illustration;

FIG. 19 is enlarged view of the claimed portion of FIG. 6 , shown separately for clarity of illustration;

FIG. 20 is enlarged view of the claimed portion of FIG. 7 , shown separately for clarity of illustration;

FIG. 21 is enlarged view of the claimed portion of FIG. 8 , shown separately for clarity of illustration;

FIG. 22 is enlarged view of the claimed portion of FIG. 9 , shown separately for clarity of illustration;

FIG. 23 is enlarged view of the claimed portion of FIG. 10 , shown separately for clarity of illustration;

FIG. 24 is enlarged view of the claimed portion of FIG. 11 , shown separately for clarity of illustration;

FIG. 25 is enlarged view of the claimed portion of FIG. 12 , shown separately for clarity of illustration;

FIG. 26 is a front view of the first image in a sequence for a display screen or portion thereof with transitional graphical user interface showing my new design with different broken line disclosure according to a second embodiment;

FIG. 27 is the second image thereof;

FIG. 28 is the third image thereof;

FIG. 29 is the fourth image thereof;

FIG. 30 is the fifth image thereof.

FIG. 31 is the sixth image thereof;

FIG. 32 is the seventh image thereof;

FIG. 33 is the eighth image thereof;

FIG. 34 is the ninth image thereof.

FIG. 35 is the tenth image thereof;

FIG. 36 is the eleventh image thereof;

FIG. 37 is the twelfth image thereof; and,

FIG. 38 is the thirteenth image thereof.

The outermost broken lines in the drawings depict a display screen or portion thereof and form no part of the claimed design. The remaining broken lines in FIGS. 1 - 13 and FIGS. 26 - 38 depict portions of the transitional graphical user interface that form no part of the claimed design.

The appearance of the transitional graphical user interface sequentially transitions between the images shown in FIGS. 1 - 13 and FIGS. 26 - 38 , respectively. The process or period in which one image transitions to another image forms no part of the claimed design.

The grayscale in the drawings represents a contrast of appearance.