I had the exact same issue with my roommate and ended up using Share-A-Cart. It works really well and I have no complaints. Basically, it is a handy tool for sharing carts that lets you send your entire Walmart cart to another account with one click. We are super satisfied with it because it bypasses Walmart's buggy native sharing.

🙌

Building on the earlier suggestion of Share-A-Cart, that extension route works really well, but you need to be careful with how they handle session data. Since Walmart doesnt have a public cart API, these tools scrape the page DOM and copy local storage states. Just a warning: if you edit the cart simultaneously, it can desync. I had a bug where it duplicated items at checkout because we both had the page open. Also, keep an eye on permissions. Some extensions grab session tokens, which is a security risk if they get compromised. Another option is sharing a Walmart registry list, though it lacks one-click checkout. TL;DR Share-A-Cart is the best option, but avoid editing the cart at the same time to prevent duplication errors.