Hi,
If the payment log file is empty, then it means that HikaShop doesn't even need to ask the plugin for the available shipping methods.
For example, I can see that you select the USA country in the "zone" restriction setting.
This means that if the shipping address currently selected on the checkout is not in the USA, the shipping method will be discarded automatically, without even asking for the plugin to do anything, and thus not contacting FedEx, and not adding anything to the log.
Ideally, I would recommend leaving the restriction settings (zone, warehouse, currency) out for now so that they don't interfere. You can always add them back later, one by one if you need them.
If that doesn't help, there are two things left:
- If other shipping methods are available, the system won't display to the user error messages from other shipping methods (for example, if you set a min weight and the cart of the user is below that weight, it's normal the shipping method is not displayed to the user, so you don't want an error message to be displayed). So, you can disable the other shipping methods temporarily and only leave this one published. That way, if there is no shipping methods found during the checkout, HikaShop will display an error message specific to the issue regarding that shipping method. That should allow you to find out what the problem is.
- You provided several screenshots, but not for some of the settings like weight unit, special service type, etc. Some of these settings can affect what is returned by FedEx. For example, if you select the weight unit "lb" and you're located in Europe, or you select the weight unit "kg" and you're located in the USA, it's possible FedEx will refuse the request for the rates. Normally, with this example, this should display in the logs and as an error message (see previous point).