That's a wildly complicated idea that fails an even passing test of logic or evidence. Presidential elections are 50 different systems run by thousands of counties. You'd have to create tens of millions of fake ballots, somehow make then undetectable, fold in republican lead election boards under Republican secretaries of State, under Republican governor, overseen by a Republican appointed Attorney General and a Republican administrations CISA. There are democratic non-profits, thousands upon thousands of 'mules', voting county companies, Chinese hacks of software, firefights between the CIA and the US Army, North Korean submarines, and the ghost of Hugo Chavez.....all working together to throw an election for Biden for this fantastically elaborate conspiracy to work.
Or....an unpopular incumbent in a struggling economy just lost.
When you hear hoof beats, think horses. Not zebras.