Import products into woocommerce.
This plugin certainly works well for simple spreadsheets. You start by importing a spreadsheet template of just the field names (not the values). You then map these to Woo Commerce product fields. If there isn't an equivalent Woo Commerce field you can create your own custom ones in Woo Commerce first them map your spreadsheet template fields to those.
It does, however, have one major downside with large number of fields. Once you import you fields you can't go back an edit them after. My client's spreadsheet had over 20 fields - mostly to output into custom templates. If I even made one mistake mapping any of these to Woo commerce fields I would have to start again - no going back.