Are there historical cases of country A printing the currency of country B for the main purpose of economic warfare?

Slightly different but perhaps relevant. A friend of mine spent some time during the late 1960s transporting counterfeit American Express Travelers Checks into Laos, that the CIA was using to fund its operations. He traveled on US military transport aircraft from Saigon to the capital of Laos (whose name I forget). The amount was significant, suitcases full. Apparently this was done with the tacit acceptance of American Express. He never told me who he passed them to in Laos but I presume some warlord paid for them with discounted cash, and I suppose that they stayed in Laos being used as a medium of exchange, and were rarely if ever presented to AmEx for redemption.

Very obscure historical example:

From 1287 to 1295, the Danish nobleman Stig Andersen Hvide was leading a band of outlaws from the island of Hjelm supported by the king of Norway against the king of Denmark. Stig managed to kidnap expert coin makers and bring them to Hjelm, where they produced counterfeit Danish coins.

This allowed Stig and his supporters to buy up all the supplies they wanted in Danish merchant cities. The heavy inflation and the problems it caused for the Danish economy made it difficult for the Danish king to afford assembling an army against Stig.

https://en.wikipedia.org/wiki/Operation_Bernhard (an exercise by Nazi Germany to forge British bank notes. The initial plan was to drop the notes over Britain to bring about a collapse of the British economy during the Second World War. )

David Petruccelli writes in "Banknotes from the Underground: Counterfeiting and the International Order in Interwar Europe"

In December 1925, a group of Hungarian nationalists were caught trying to put into circulation a large quantity of counterfeit francs in a bid to weaken the French economy and fund irredentist action in Central Europe.

Edit:
Though not officially sanctioned by the government of Hungary, some high ranking officials were involved. Quoting from Andor Klay's "Hungarian Counterfeit Francs: A Case of Post-World War I Political Sabotage":

...the nation's highest-ranking police official, Nadosy, admitted to the ministers of justice and interior that he had personally issued special documentation for the arrested "couriers." Next it became known that a former minister of supplies, Prince Lajos Windischgraetz, was also implicated.