Combining multiple metabolomics data sets

Is it possible to combine multiple metabolomics data sets from various tissues (in my case, feces, serum and urine)?

I tried uploading serum and fecal metabolites and OmicsAnalyst never concludes processing or shows any errors. I am guessing perhaps since I have different metabolites in each of the metabolomics data sets, this is causing the issue? Or does OmicsAnalyst generally not accept two of the same omics data types?

This was not in our mind when developing OmicsAnalyst. It is possible to add this feature support since they are essentially different matrices. It will be helpful if you can share the data and elaborate on your analysis goal.