You can create a custom split button from the model to create a specific form type.

Create a custom split button for the model

In the model document type in configuration click on the new Custom Split Button.

To add a new custom split button click on Manage Custom Splits button under the form type configuration.

The in the new pop up window you can click on the "Add New Button" to create a new Button.

Give the button a name.

Select the form type you wish to split to when the button is clicked.

You can also configure whether the button appears in the toolbar as well as the document list user field if it is configured on the form type.

After adding the row and setting the options as needed, click save on the row to create this custom split button.

Create a new form using the custom split button from the model

Select the object you wish to split from.

Then click on the custom split button to create the specific form.