The importing is part of the Power add-on, the others (enhanced etc) are part of experience add-on. They are two separate add-ons
Refer to the Import documentation for information.
https://docs.storelocatorplus.com/blog/power-import-and-wpslp-4-9/
with Power add-on the import process is done via a cs file. If you need to export locations before upgrading your site that is also a Power add-on feature.
https://wp.storelocatorplus.com/product/power/
To get both and all the other features you could buy Premier subscription.
see the product details for both/all.
You can also check the Buyers guide.
https://docs.storelocatorplus.com/blog/most-common-what-should-i-buy-questions/