Importing from old website is not working

Hi, we have tried to export products from the old website panel and import them into the new one using the import/export WordPress tool that can be found on the top of the products page title and, in one hand, there is no attribute “swatch” or anything that appears to be related to this plugin on the CSV file, no column or field value that could contain images or color values used on the old site attributes.
And, in another hand, how we expected, once we have performed the import operation into the new site no attribute color or images was imported.
You could ask us whatever you want in order to fix this issue if it is possible, we need to fix this issue in order to publish new site ASAP. Thanks for your time, we will appreciate your help.