You can publish your products in bulk to your sales channels by going to your Products page > Bulk Manage > select Update Existing Products > Click on No, I need to download a list of my products > Select all Sales Channels within Sales Channels. Click on Build Product Sheet and Download Product Sheet. This will download a CSV file of all your products. Under the columns for the Sales Channels, set the value to TRUE. Save and re-upload the file to publish your variants.