Modify and Customize Magento 2 Webkul Addons

Task 1 Mass upload addon, with marketplace addon: add a functionality, where each seller will be able to add their own shipping, and be able to give free shipping after their predefined amount. • For example: There are two sellers, A and B. Seller A wants to ship with courier x, and make the shipping free after 50 euros. Seller B ships with courier z, and has no free shipping • Buyer E places into his cart items from seller A worth 50 euros, and items worth 50 euros from seller B. • The cart shows free shipping for items from seller A, and x amount for items from seller B Task 2 Mass upload addon: Currently the seller can mass upload their products via csv or xml. However, the XML is not synchronized with the cron, thus stock control cannot be renewed with cron settings. We need a customization, where the seller will be able to add in the same manner as now the xml feed, but with the click of a tickbox choice to be able to add in the cron settings (with a label ‘Live Sync), thus the feed of the xml will be updated depending on the cron settings, so the database is renewed. Task 3 Split cart addon Currently the split cart addon separates each order from each store, and the user has to manually checkout and pay from every store one by one. This is difficult because it retracts the buyers from buying. We need the cart to separate the orders from different stores, show to the user that they are buying from different stores, but checkout all at once, making separate orders within the system. Something like what amazon does: It shows you that you are buying from different sellers, but you buy once altogether, and the orders split within the system to go to each seller.