The regulation that impacts this is found at 31 CFR 411.1.
There are very particular requirements. You'll want to read the reg carefully.
PART 411--COLOR ILLUSTRATIONS OF UNITED STATES CURRENCY--Table of Contents
Sec. 411.1 Color illustrations authorized.
(a) Notwithstanding any provision of chapter 25 of Title 18 of the
U.S. Code, authority is hereby given for the printing, publishing or
importation, or the making or importation of the necessary plates or
items for such printing or publishing, of color illustrations of U.S.
currency provided that:
(1) The illustration be of a size less than three-fourths or more
than one and one-half, in linear dimension, of each part of any matter
(2) The illustration be one-sided; and
(3) All negatives, plates, positives, digitized storage medium,
graphic files, magnetic medium, optical storage devices, and any other
thing used in the making of the illustration that contain an image of
the illustration or any part thereof shall be destroyed and/or deleted
or erased after their final use in accordance with this section.