Just wondering, what would happen in this experiment.

In the experiment you would first have two entangled particles.

Then you fire one of the particles, lets say "Particle A", at a double slit towards a detector.

While in transit to the detector, what if the other entangled particle, lets call it "Particle B" was observed / had it's wave function collapsed?

Would "Particle A" still generate a wave-like interference pattern or would the wave function for both be collapsed?

In theory you cannot send classical data by entanglement, so this experiment must somehow fail, but I can't quite figure out why. If this experiment were to succeed, then you could read and send data about wave function states over entangled particles.