Updating our ebay store and setting up store on other platforms

We are looking to expand our online bookstore presence by updating our existing eBay store and establishing new stores on other platforms. Specifically, assistance is required to optimize our eBay store interface and inventory listings. In addition, setup of companion bookstores on Facebook Marketplace and TikTok is desired to broaden our customer reach. An efficient bulk uploading process utilizing an Excel inventory document would be invaluable, as we have thousands of book titles currently listed on Amazon. The ideal candidate will be well-versed in platform-specific listing and storefront best practices for eBay, Facebook, and TikTok. Experience designing an intuitive bulk data import workflow for rapid cross-posting of inventory across multiple sales channels would be particularly beneficial. Please provide your qualifications and proposal for helping scale our online bookselling operations in a streamlined, cost-effective manner.