As everyone is probably aware you cannot do item fulfillment or item receipts via CSV, has anyone created a script that allows you to do bulk updates to item fulfillment from a CSV upload? Looking for solutions to this issue.

This can be accomplished. We built a custom pre-fulfillment record and then have an M/R script create IFs as a derivative. We wrote a blog on this subject back in March highlighting the solution: https://extendtech.net/multifulfillments-a-netsuite-item-fulfillment-challenge

Can’t you import to the Fulfill Orders page? This creates Item Fulfillment's