According to patent filings in the US regarding "Plasma Stealth" (which is what I assume that the OP is referring to), there is absolutely a possibility of using a uniformly distributed plasma boundary layer over a solid to interfere with the transmission of Electromagnetic waves through the plasma in both directions. If properly tuned, it can indeed absorb an incoming wave, reflect the wave, or, in a very clever bit of math, actually cancel the wave out during it's reflection. Here's where it gets tricky: like any "coating", it is tuned to a particular frequency/wavelength of radiation. If it sees a wave that it isn't expecting, instead of canceling it out, it could potentially amplify it until properly tuned. Also, if it gets a wave that matches the resonant frequency of its current frequency, instead of absorbing or canceling the wave, it can "ring like a bell" and effectively massively amplify the return signal. It is also minimally effective against low frequency EM radiation.
As compared to proper stealth airframe design, applied or intrinsic RAM coatings/materials, and other EM reflection techniques, plasma stealth is:
Just as susceptible to long range search radars (it can't handle the fact that the wavelength is greater than the boundary layer that it has to live in among other things)
Is more effective a some frequencies than others, but, unlike a fixed configuration stealth construction, it is tunable to a certain extent, but it also has a reaction time and is disruptable.
Is subject to system failure (plasma generators are finely tuned machines and can react poorly to environmental conditions, changing atmospheric pressures, and stresses from G-loading), intrinsic stealth is a structural component, less prone to failure (though coatings can ablate over time).
unproven in the full flight and environmental regimen that combat aircraft are expected to operate in
can even visibly fluoresce under the right circumstances (if it gets a strong enough dose of EM radiation that it must absorb, it will have to dissipate that energy through EM emissions of its own, across a wide spectrum including visible, infrared, and UV)
All that being said, for something like a bomber, which isn't going to be performing any high G maneuvers, and tends to fly a straight and level flight path, it may actually be a game changer. Bombers typically have a continuous and largely unchanging airflow pattern over their airframes. This would allow a plasma boundary layer to be created along their surface with minimal airflow disruptions. It has a large fuselage area to contain the large number of computers and mass of electronic equipment that will be needed to control the various plasma generators throughout the airframe. It has a large payload capacity to handle the weight of the whole system without negatively affecting the actual combat performance of the platform. If someone could perfect the system enough to be useful on such a platform, it would give the user a truly stealth bomber with a largely conventional airframe with conventional materials. Something as simple as a commercial airframe could be made into a highly effective night bomber that is as stealthy as the B-2. If combined with even modest amounts of stealthy airframe design and even basic RAM, it could be almost undetectable until its almost on top of its target.
All that is based on a bunch of IFs though. Air is not a uniform fluid. There will be minor variances in air pressure constantly impacting on the plasma boundary layer, which will reduce its performance. Being able to deal with this will be an immense challenge.