I have produced a Dash Jump "Macro" in Steam Input and shared a Xbox Controller Community Layout with these macros bound to the D-pad. Look for the below.


The layout uses keyboard inputs (Preset 1) since the game was giving me binding issues with my 8Bitdo Ultimate C (e.g. Menu = R-stick click, etc), you may need to disable gamepad input in the Ys VI configuration tool for it to function properly. Simply press the corresponding D-pad button to Dash Jump in that direction.

If you have an Xbox controller then this should be the end of the guide. Try the layout out, tweak it to your liking and have fun. 😁

If you would like to know how to apply this to other controllers, read on.

I have been putting "macro" in quotes because Steam Input doesn't have a true scripting feature unlike Autohotkey. You can, however, work around this using Fire Start Delay to queue up the key presses. Follow this pictorial guide.
In summary pressing a direction button should trigger the following

1. Tap Direction
   
2. Wait 300ms
   
3. Tap Direction again
   
4. Wait 50ms
   
5. Tap Attack and Jump

When set to the default "Regular Press" activator, the input duration relies on how long you hold the button down physically. I am personally unable to keep the button tap timing consistent which was the major reason I couldn't perform Dash Jumps. It seems that the window which the game considers a "light tap" is very small. Hence why "Start Press" activators are used instead.

The first direction input / Command 1 turns your character towards the direction of jump since that is another (annoying) requirement to Dash Jumps. If you choose to manually turn your character, you can omit this command. In this case, you might want to reduce the waiting time in Step 3 (300ms) to zero as well.

I initially used a 200ms waiting time suggested in Slaynie's AHK guide, but it produced inconsistent results. The 300ms time is obtained after some testing with my own controller. You may need to fine tune this 300 value when using a different controller

The idea of using a macro and the logic behind it is from Slaynie's AHK guide, credit to them.
https://cs2bus.com/sharedfiles/filedetails/?id=436774313