Does it sync between locations?
No. SKU Stock Sync does not sync inventory from one Shopify location to another.
Inventory is synced within the same Shopify location only. If the same SKU exists at two different locations, SKU Stock Sync treats those as separate SKU/location groups.
For example, BLACK-SHIRT at Location A and BLACK-SHIRT at Location B are separate groups.
This keeps inventory aligned with Shopify's location-based inventory system and helps prevent stock from one location being copied into another.