They are both foreign citizens who have appeared on behalf of U.S. political candidates. For the FEC’s explanation of why such volunteering by foreign citizens doesn’t violate U.S. election law, see the Elton John / Hillary Clinton decision, or this discussion from 2008.
On the other hand, a foreign artist may not contribute intellectual property for further resale. That FEC advisory opinion concluded that the artist’s letting a campaign committee produce a “limited edition [of prints] from the original works of art (gouaches) created” by the artist — for fundraising purposes, with no payment to the artist — would be a prohibited “contribution” by a foreign national. I don’t know who the foreign artist was there.
Thanks to Mike Bayes for the pointer.