Is there a term for two polygons with the same angles but different side lengths?

"Angular congruence", perhaps? I see it used occasionally, most clearly in http://www.gutenberg.ca/ebooks/dantzig-poincare/dantzig-poincare-00-h-dir/dantzig-poincare-00-h.html:

Thus, two rectangles may be dissimilar, although the corresponding angles are certainly congruent in this case; again, the sides of any rhombus are certainly proportional to the sides of any square, and yet the two figures are generally dissimilar. Angular congruence does by no means entail proportionality of lines.

The case of two similar triangles is an important exception. Here the congruence of corresponding angles does entail the proportionality of corresponding sides and, consequently, the similarity of the two figures. This property of similar triangles enabled Euclid to eliminate allusion to proportion and reduce the criteria of similarity of two polygons to congruence tests.

(Italics in original; bold face mine.)