The short answer is: Yes
However, there is more to it than just supplying 3v3 power.
Experience has shown us that the Omega2 is very sensitive to power fluctuations, requires a regulator at least, but a couple of caps are highly recommended together with the use of short, heavy gauge wire due to the current drawn when hitting wifi initialisation at boot.
Your first port of call should be the official documentation here: Powering the Omega with No Dock
Next, doing a quick search of these forums will yield a fair amount of discussion from the enthusiasts here on their own experiences and suggestions on making it a smoother experience for you.
Here is just one thread of many: [Resolved] Omega 2+, Powered without Dock, Shuts off after 18s
Having said all that, do not underestimate the power of having a spare expansion dock available when things go wrong. It is by far the simplest way to power your O2 and get direct serial access to the console for troubleshooting.
Welcome and Good luck !!