Conversagent has several options available for your Virtual Human. You can select, or change, your character in the Configuration menu. To change the selected character click the Edit Widget Settings button on the bottom-right of screen.
Click the image of the character you want, then click Update at the bottom of the screen.
Now, when you use the Test Widget Now feature, you will see the new character you have selected.
If you have already deployed your widget to your website, you will have to copy in the new code generated on the Add to website screen, to see the new character on your site.