Hello kmirsalehi,
Here’s a helpful forum post that I believe should help your use case: Change the cursor when one specific tool is active - #10 by dfelix
Essentially, in the constructor of the custom tool you are overriding the cursor property while the tool is equipped. In your case, the value of cursor would be “crosshair”.
Let me know if this helps!
Best Regards,
Jacob Romano Carlsen
Web Development Support Engineer
Apryse Software Inc.