Is elastomeric paint capable of spanning hair line cracks between 2 dissimilar materials and prevent leaks? Stucco and a plastic stucco expansion joint.

The exterior brick on my home is currently painted with semi-gloss paint, and I’d like to paint over it with a flat paint. What are the steps that I should follow?

I painted my cabinets with a oil base primer and paint. My question is; Should I also paint the cabinets with a sealer?