This is a conspiracy theory with no evidence given. Recurring pro-Kremlin narrative presenting colour revolutions as attempts by the West to overthrow regimes in post-Soviet states and in other regions. This narrative portrays any spontaneous disorders and civil uprisings in other states, especially the former Soviet republics, as West-funded "colour revolutions".
There was no coup d'etat in 2018 in Armenia, but peaceful protests of hundreds of thousand people in response to Serzh Sargsyan's third consecutive term as the most powerful figure in Armenia.
The Prime Minister of Armenia assured that he has no shadow obligations to anyone, since he received money for the revolution from ordinary people.
We spent about $200 thousand on our revolution. Where did this money come from? We asked the people. We had an electronic wallet, and Armenians from all countries, by the way, mostly from Russia, gave us money. We spent this money, and every week during the revolution we published how much we spent and for what.
The narrative has been applied, among others, to report about protests in Ukraine, Venezuela, Georgia, and Belarus, as well as to portray the West as an aggressive actor constantly preparing new coups.
Read also similar cases claiming that the West is a threat to national values: the Istanbul Convention will destroy traditional families, it is attacking identity and traditions, that an influx of 50 000 perverts is expected from abroad, convention is a threat to the Armenian Army, Soros foundation is organising clashes in Armenia, serving foreign agendas aimed at the collapse of Armenian statehood, and that Armenia is occupied by Soros.