I am good with Mashup but not a lot of experience with angular portals.  This isn't getting a lot of responses so though I would see if we could get you started.

A Mashup requires you to define a <script> tag for getting the Mashup scripting and <DIV> element containing definition of the Mashup.

I would think you would want to create a angular component for each Mashup and then add the <script> reference and <DIV> content to component.html.

Component: mashup-createNewWork

mashup-createNewWork.component.html:

<script src ='https://[PRPC_HOST]/prweb/PRServlet?pyActivity=pzIncludeMashupScripts&disableCompacting=true'></script>

<div id='testNewWork' style="overflow:auto" data-pega-gadgetname ='GadgetTestNewWork'
data-pega-action ='createNewWork'
data-pega-action-param-classname ='PegaSample-Task'
data-pega-action-param-flowname ='BasicProcess'
data-pega-action-param-model =''
data-pega-isdeferloaded ='false'
data-pega-applicationname ='[APPNAME]'
data-pega-threadname ='STANDARD'
data-pega-systemid ='pega'
data-pega-resizetype ='stretch'
data-pega-action-param-parameters=""
data-pega-url ='http://[PRPC_HOST]/prweb/IAC'>
</div>

The template part of the component could also be used to specify the div instead of using the component.html.

Does this get you started?