That’s exactly what Microsoft Power Automate can do, along with a host of other automated actions. ... Create a new flow in Power Automate, and then click Describe it to design it.

Custom actions work like any other action, appearing as action blocks in the Power Automate for Windows canvas. However, it’s important to note that they’re not for all your users.

As Microsoft notes, currently the tool works best with Microsoft 365 apps and services; even so, I was able to use it with common Power Automate connectors like Twitter or other social media.

Often people create flows to call Microsoft Graph end points or Approval from within Power Apps rather than "Power Automate connector actions" from within Power Apps.

Ignite 2019: Microsoft is continuing to add more features to its Power Platform, the collection of low-code and no-code tools including Power BI, Power Apps and Power Automate.