Looking for integration shipping software can connect multiple stores

Hi friends,

I sell on Amazon, my own website, and Etsy. Currently, I'm getting labels from Pirateship and directly from Amazon. I'm looking for a fulfillment software/website which can integrate orders from all my sale channels so I can just get the label from there, easy to manage and filter which order is due date to ship first across all stores.

Seem like Pirateship can't integrate with Amazon. I know Shipstation can do this but we have to pay monthly subscription. Does anyone already use Shipstation? or any recommend for a software/website which can do the job? I wonder how much cheaper/ discount the label can be.

We normally ship about 200-300 packages per month and the weight is 12 oz - 1.6 lb by USPS.

Thank you so much for your advice!!!