It doesn't matter how you name those parameters really. It comes down to the same, just like you say
It is just important to keep in mind that your game code will set the parameter values, which the conditions will check.
I would in your case just have one parameter "forward" or so.
And depending on the control scheme in your game you can set that value to either true or false. If you use a game controller check the stick. If you use keyboard, check the cursor up key for example. The state machine doesn't know about the keyboard or game controller, just about the parameter "forward".
Both the outgoing transition condition from idle to shuffle and from jump to lean forward can check the same "forward" parameter.