I let CII to select spring hanger with hardware weight (HW) is included.

The hanger report is showing:
+ Spring rate
+ Cold load
+ Hot load which is including HW

The restraint summary is showing Hot load but not including HW

Now I input SR and CL back into pre-define hanger data and re-run. I check restraint summary, there is no difference in output if delete or keep HW, and HL is including HW. By logic, HW shoud be remained since I think HW likes an downward force together pipe weight acting on the spring hanger.

Is it OK to delete HW or remain it?

Since you fully defined the hanger,the value of CL that you inserted take into account also the hardware load, therefore it does not matter anymore if you keep or delete. It was useful at the stage of spring design. You can keep for record. I did not check but maybe there is a difference in displacements (or it should be) If this is the case, keep the HW do not delete in any case.

Where the spring is above the pipe, this additional hardware weight is an added load on the spring but not on the pipe. You see that the spring is selected with this additional load. The restraint report shows the pipe load on the restraint and this added load pulling down on the spring plate is not included.
You have a point though, if you wish to enter the program-selected spring data into your model, there is no accounting for that extra load unless you model that added load in some other fashion (e.g., add a force at the hanger node).

OK, instead of adding a force at hanger node. I will insert a short rigid element with weight (HW) at hanger node. This will avoid impact on load case setup.