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 second image thereof;

FIG. 3 is a third image thereof.

FIG. 4 is a fourth image thereof;

FIG. 5 is a fifth image thereof;

FIG. 6 is a sixth image thereof;

FIG. 7 is a seventh image thereof.

FIG. 8 is an eighth image thereof;

FIG. 9 is a ninth image thereof;

FIG. 10 is a tenth image thereof;

FIG. 11 is an eleventh image thereof;

FIG. 12 is an enlarged front view of a portion of FIG. 1 , shown separately for completeness of illustration;

FIG. 13 is an enlarged front view of a portion of FIG. 2 , shown separately for completeness of illustration;

FIG. 14 is an enlarged front view of a portion of FIG. 3 , shown separately for completeness of illustration;

FIG. 15 is an enlarged front view of a portion of FIG. 4 , shown separately for completeness of illustration;

FIG. 16 is an enlarged front view of a portion of FIG. 5 , shown separately for completeness of illustration;

FIG. 17 is an enlarged front view of a portion of FIG. 6 , shown separately for completeness of illustration;

FIG. 18 is an enlarged front view of a portion of FIG. 7 , shown separately for completeness of illustration;

FIG. 19 is an enlarged front view of a portion of FIG. 8 , shown separately for completeness of illustration;

FIG. 20 is an enlarged front view of a portion of FIG. 9 , shown separately for completeness of illustration;

FIG. 21 is an enlarged front view of a portion of FIG. 10 , shown separately for completeness of illustration; and,

FIG. 22 is an enlarged front view of a portion of FIG. 11 , shown separately for completeness of illustration.

The outer perimeter illustrated by a pair of dashed broken lines in the drawings illustrates a display screen or portion thereof and forms no part of the claimed design. The remaining broken lines in the drawings illustrate portions of the graphical user interface that form no part of the claimed design.

The dot-dash broken lines delineating portions of the claimed design illustrate boundaries of the enlarged views and form no part of the claimed design.

The appearance of the transitional image sequentially transitions between the images shown in FIGS. 1 - 11 and FIGS. 12 - 22 , respectively. The process or period in which one image transitions to another images forms no part of the claimed design.

The stipple shading in the figures illustrates a contrast of appearance, such as a color contrast, and forms part of the claimed design.