I've been living in the Netherlands for half a century now, and I have witnessed several times that 'coins' with a nominal value were minted on the occassion of an important jubilee in the history of a particular city or town, and that these coins were said to be valid currency in the named place.
Acceptance of them was at the will of shop owners, but usually, people bought these coins as a souvenir and didn't intend at all to spend them. Furthermore, I doubt if there was any legislation backing the exchange value of these items.
So in a way, these coins could be used as currency, but can probably not be called 'Legal Tender', and the degree of circulation was extremely low, and only within the context of the celebrated event.
My examples are the coins commemorating the 700th anniversary of Amsterdam in 1975:
Perhaps my Dutch fellow members have more of these examples and stories.