How do cholinesterase inhibitors affect tau proteins and beta amyloid that form in alzheimer's disease?

They don't: The cholinesterase inhibitor group of drugs are not disease modifying agents, and merely improve synaptic connections by preserving the lower levels of acetylcholine in the brain. However, there is no direct or indirect effect on the tau or amyloid presence.

They don't : Cholinesterase inhibitors inhibit the breakdown of acetylcholine essentially giving the brain longer lasting acetylcholine. The neurotransmitter is involved in attention and memory and probably many other things. This neurotransmitter is in short supply in alzheimer's, lewy body dementia and other illnesses. They do decrease anxiety, agitation and psychosis.