Enable element templates in Property Panel

When specify customElementTemplate as Object, template load mechanism is not handling Object. It takes template as function or array.

reload debug
Screenshot_4

setTemplates:

setTemplate is throw error. Is it not the valid templates, validTemplates is empty array. Screenshot below.

Screenshot_5

When debug the camunda-modeler the loadTemplate is a function. It fetch from the resource/element-template/*.json folder.

Screenshot_6

Is there anything Am I missing here. I used the same element template (EmailTask.json) works fine in camunda-modeler but not in bpmn-js moddle.