Is this what you are wanting? I use it on my mouse so I don't have to hold down the mouse button. The only drawbacks are you cannot delete inspirations out of your tray (this impacts Awakens) and you cannot bulk sell salvage to the vendor.
Remapping Your Mouse to Control Your Movement
If you are not satisfied using your keyboard to control all your movement, you can bind navigation and movement keys to your mouse buttons to give you greater mouse control. The following examples assume you have a four button mouse:
/bind RBUTTON "+forward$$+mouse_look" or just
/bind RBUTTON "$$+mouse_look"
/bind LBUTTON "-mouse_look"
/bind MBUTTON "map"
/bind BUTTON4 "+up"
/bind LSHIFT+RBUTTON "+backward$$+mouse_look"
/bind LALT+RBUTTON "-mouse_look"
The first button is the basic navigation command. When you click mouse button 2, the mouse enters "mouse look" mode. The mouse pointer disappears when you move the mouse to the left or right, your character turns left or right. When you move your mouse up or down, your character looks up or down (and if flying, your character tilts up or down). Now every time you press down on mouse button 2 your character will move forward.
The second binding ends mouse look. When you actually need to use your mouse to click on something, click on mouse button 1 and your pointer will reappear.
The third mouse binding causes the zone map to pop up whenever you press mouse button 3. Mouse button 3 will probably continue to stay mapped to +camrotate, so you can still use it rotate the camera around your
character. It is alternately annoying and amusing to see one happen when you are only interested in the other.
The fourth mouse binding allows mouse button 4 to control when the character jumps.
The fifth mouse binding acts just like the first, only instead of going forward the character moves backward.
The sixth mouse binding allows me to right-click on objects with my mouse when I have the left alt key pressed down in order to bring up the pop-up menu.
From <https://cityofheroes.fandom.com/wiki/The_Incomplete_and_Unofficial_Guide_to_/bind#Remapping_Your_Mouse_to_Control_Your_Movement>