A:Answer The phone is unlocked and will function on CDMA, or GSM systems, which means that, unless your carrier specifically denies the MOTO G4, it will work with any service provider. It will need a micro, or nano SIM card, from your provider. These are usually free of charge, directly from your service provider and usually never more than a few dollars. I use TracFone and while TracFone will provide a SIM kit, for free, third party vendors, such as this seller, offer them for $1, with free shipping.
I suspect the HOTSPOT function will depend upon carrier. I know two individuals with unlocked, HOTSPOT capable phones, on VERIZON service, that require subscription to the HOTSPOT service. This is because it uses the DATA service to provide Internet access. I use a MOTO G4 with TracFone, on the CDMA band; service for which, is provided by VERIZON and the HOTSPOT functions freely. However, I believe this is because my DATA is prepaid and so, will only work until my DATA pool is exhausted. I think you will need to contact whomever you plan to use as a service provider. Be aware that the HOTSPOT absolutely devours DATA - it consumes about 50MB just to establish a connection, with my WIN7 laptop.
Short answer: YES, the HOTSPOT is 'unlocked' to enable, at will, but it may or may not actually function, with your service provider.