Yes, you can! The supported formats are ttf, otf, woff and woff2. This feature is available on Standard and Pro plans.
Here is how to do that:
Hit on the font style and then "Upload custom font".
Select your font from your desktop files.
Confirm that you either own this font or are officially allowed to use it.
Note, that some fonts may not work properly will all animations.
Enjoy the video creation!