Though there is no in game means of doing so, it is possible to remap the controls of A Hero's Call to suit your liking. To get started, do the following:
Navigate to your game's directory (wherever you extracted the game to)
find the folder named 'Data for RPG', and enter it
Backup the file Keys.config to a safe location
Open Keys.config (if asked to choose an app, select something akin to notepad or preferred text editor)
You should now have Keys.config open in notepad or a similar editor. You'll see a few lines beginning with double slashes, these are comments and not to be touched. Under that are definitions for actions, and the controls assigned to those actions, an example follows.
fp_run_forward w | right_mouse | up | gamepad_lstick_up
If we break this down, we can make several observations about ITT. fp_run_forward is the action, fp probably standing for first person'. To the right of the action is all the controls currently bound to that action. Notice that w is the first one, its simply the character, not a hex or decimal scan code, which makes it very easy to manipulate. There are some constants that you will need to know, but these can all be gleamed from the rest of the file.
In between the shortcuts is the pipe symbol, it looks like this: |. It can be accessed by pressing shift + backslash on U.S. keyboards. It is important that this symbol is placed between pairs of shortcuts, and no symbol is left trailing at the end of the line.
It is therefore easy to start making modifications to this file, and if the game will not load, or produces an error message, it is most likely related to this file, which you hopefully have made a backup of. But, there is still another consideration to make. The next point that bears discussion is conflicts. This is when the same key or control is bound to two or more actions. This would probably cause an error at game startup. It is advisable to read the entire file, noting down changes you wish to make, along with keys that currently would create a conflict, and check them off the list. An example, I changed turning to the left and right arrows, or A and D as I found I didn't often use strafing. I can then simply turn with the arrows and never stop walking to do it. I also made snap to interactables work with control arrows, where before, it would only work with control A and D. For turning,I would have a conflict with strafing, so I needed to make sure that I remapped strafing to shift A and D, as well as shift left and right arrows. This would have cleared any conflicts, since I simply took what was there and reversed it. I now have a control scheme I prefer over stock.
In conclusion, it is possible to change the keymap for A Hero's Call. By employing a bit of caution and backing up the original, it should be possible to remap the controls quite easily. The file contains a straightforward syntax, delimiting each shortcut following the action by use of the pipe symbol (|). It is necessary to consider alterations and make sure the file is clear of conflicts before the game should be started.