Through quantile normalisation, which I assume you used, it's virtually impossible for the highly-expressed outliers in A to be the same as the lowly-expressed outliers in B. I'm not sure if that's what you were implying?
It may be due to the long, lower tail that's present in one of your samples (9 samples from the right in A), which, through quantile normalisation, would affect the distribution in all other samples.
I neither believe that this is a problem in any way. I have seen elsewhere how, after quantile normalisation, lowly-expressed outliers will exist. Before deciding if this is a problem, you should take a look at:
- PCA bi-plot
- density plots of normalised counts
- pairwise scatterplot matrices
- quantile-quantile plots after differential expression analysis