Yes you can create a new calendar request from a Workflow…I believe there will be some advanced Exchange/Outlook components coming out in the future, but for now, this method should work quite well.

First of all, the component you need is not loaded by default, so you will first add this component into your components list via the Import Components button. The one you want is called VCalendar.dll and it will add a component to your list called “Creates a VCal Request”.

Once you import that, drag it into an empty project, set the title, time, description, etc. of the calendar item (can use variables of course), and then select a variable name for the output such as Vcal.

Then after that, add a Send Email component, and for the attachment of the email, point to the property “Vcal”, which of course refers to the output name of the Creates a VCal Request component. So you generate the calendar item with the first component (which will create a .vcs file), and then you email it to someone with the Send Email component. Outlook can consume a .vcs file.  Below is a screenshot: