Hello,
I'm a PHP developer that has extensive knowledge in writing scripts to utilize the APIs of other websites.
In the past month alone, I've already delivered 3 projects, utilizing Paypal, CloudFlare, and WordPress APIs (you will find reviews by the respective project owners if you open my profile).
I could write a script that would have your listings extracted from Etsy, and that would allow you to add more listings (assuming Etsy's API already allows that).
The delivery will be within 3 days, basically 2 days for writing it, and a 3rd day for testing.
If interested, we could chat to discuss further.
Regards,
Amr