What features would you like to see in Pixelmator Pro?
Where available, you can use Italics to slant text but I have a feeling that's not exactly the feature you had in mind. A few other ways you can slant text in Pixelmator Pro would be by skewing it (choose Edit > Transform to turn on the Transform tool) or applying the Perspective Transform effect. The first method converts text into shape, so it's best to use it when you're done editing the text itself. The second method is completely nondestructive, meaning you can still edit the text after you've transformed it. A downside of the second method is that it can be a little less precise.