A recurrent pro-Kremlin narrative about the influence of the West in the political process in the former Soviet republics.
There is no evidence of US and EU interference in elections in Belarus or Moldova. In a statement published on 02 November 2020, after the first round of the presidential election in Moldova, the EU said that "The European Union fully supports the strengthening of democratic institutions in the Republic of Moldova" and underlined that the OSCE/ODHIR Election Observation Mission did not find any serious deviations in the conduct of the election campaign and the elections.
Concerning Belarus, in a statement published on 3 June 2020 (2 months before the election which took place on 9 August 2020), the Missions of the United States, the United Kingdom, and the European Union on behalf of the EU Member States represented in Minsk, called the Belarusian authorities "to take the measures necessary to hold a safe, peaceful, free and fair election and to ensure fundamental freedoms".
The protests that followed in Belarus after the presidential elections erupted to contest the results, which were not monitored by independent experts and are largely considered fraudulent by both international observers and a big part of Belarusian society. On 19 August 2020, the European Council called the Belarusian elections neither free nor fair.
See here a similar case claiming that the West interfered in Moldova to help Maia Sandu win the presidential election and that the USA conditioned Maia Sandu's victory, or another case claiming that Poland and Lithuania control the coup in Belarus.