Is it possible to sketch, draw, free hand on FCPX? I own a Wacom tablet.

We don't know what you are trying to achieve so it is hard to answer that without you providing some more details.

You are right, I'm not sure how to formulate the question, but I'll try:

I'd like to be able to free hand write, sketch, annotate, etc...in my videos, real time, say, if I'd like to point out in the video a specific are with an arrow, circulate with a line, write on the video...I'm not sure how to call it, if it falls in animation category, if I need After Effects or Motion, or can it be done directly on the NLE? I suppose I'd need a Wacom tablet of sorts, which I do own for Photoshop work.
I apologize if my explanation is not clear and thank you for your time,

Erick

Largely NO, but to an extent, yes. Depends on the sophistication and "real time" abilities you need.

Anything you can create as a character can be put into a storyline using the title generator. That includes all the shape primitives from any "dingbat" style font. So brining in an Arrow, or a highlight circle and overlaying it is a snap.

You can then make the object as large as you like and use the position, rotation and skew controls to affect them just like you would any other piece of type or graphics, including key framing.

It's not near as convenient as, for example, the annotation tools in a program like ScreenFlow - but it's perfectly possible inside X.

It's not actually "hand drawing" because there are no drawing tools inside X. There ARE tools in Motion that let you animate stroke objects on - so that's one way. Or you can do a transparent layer in a true drawing program and matte the result inside X, but no drawing tools are built in.

To pique your thinking and see what's possible about X as a graphics manipulation tool enjoy this! - Done ENTIRELY in FCP X - it's honestly amazing. SISKIN RIVER on Vimeo

Story about it's creation here: Old-school magic in FCPX : a breath-taking combination (http://www.fcp.co/final-cut-pro/articles/1571-old-school-magic-in-fcpx-a-breath-taking-combination)