:help langmap
You can remap keys in command mode but leave them intact for typing. This means you can use the intent of hjkl - adjacent homerow keys for scrolling - by pressing the positional equivalents on your keyboard. Suppose your layout is Dvorak, then those same keys are dhtn. We need to map all four, even h:
:set langmap=dh,hj,tk,nl
You can now navigate using dhtn. This won't affect :commands like this
and won't change insert mode (i.e. pressing t will give you a 't').
You'll need to map other keys too for normal mode - for instance, the delete action would normally be d but that's now a navigation key. j, k or l might work since they're no longer navigation keys.