I am not familiar with JmatPro. I did a quick search and it seems there is an export to LS-DYNA from JmatPro. What is the material output? What is the LS-DYNA *MAT_ card written by JmatPro?
Are you trying to do welding simulation? JmatPro has been used with LS-DYNA for welding:
If JmatPro exports the correct *MAT_ material card, then you can import this *MAT_ card in Ansys WB LS-DYNA (Mechanical) using a command snippet under the appropriate body:
Let me know if this helps or not.