A heatpump is an AC, definitionally. There is no major difference for a 9000 BTU heat pump and a 9000 BTU AC in terms of capability to cool. They both work through using gas to move heat from the inside to the outside of the building.

A heat pump can just run in reverse, and move heat form outside the building inside.

A mini-split is a version of a heat pump where it has its own head and its own radiator, that are split. this is opposed to central AC.

Wait, that doesn't make sense to me. Are you talking about air heat pumps, or geo heat pumps here? The air ones are literally just ACs in a different shape, and the latter is basically an AC where the outside bit goes underground.

The principals are the same, and they even use the same terminology. I know other countries dont' differentiate in the slightest and just call them all the same thing.

There are ones with broader operating ranges. I have a Carrier infinity that cools just fine in the Saskatchewan heat and heats down to -15. I've seen some models that can operate to -25 or 30.

And yes, AC is a one-direction heat pump. The heat pumps that provide heat are an AC that can reverse the refrigeration loop and force heat into a space rather than out of a space.

Then you haven't done very good research... My Gree Minisplit heatpump has no issues cooling in the hottest days.

Then you've been lied to. My heat pump keeps the house cool when it's 40C, and warm when it's -40C.

@Luci @wildbus8979 this may have been true a decade ago but now the cold-climate versions can operate at 100% down to -20C. Ours was operational at -29C and running at about 80% output (even though according to the specs thermal shutoff is -28)