Assuming the possible provider products are all quantative reference of the respective providers this will give you the name and ID of the processes, executed in openLCA (as sql):
select name, ref_id, count(f_quantitative_reference) as multiple_providers from tbl_processes group by name, ref_id having
count(f_quantitative_reference) > 1
This could be expanded to give you also the name and ID of the product or waste.