OpenBSD LiveUSB ...
 

https://sourceforge.net/projects/liv...e=typ_redirect

It is viable this option ?

couldn't find another BSD liveCD-DVD-USB !

tia

I use E2B (Easy 2 Boot) to carry a couple dozen live-cd distributions with me, but most of them are Linux. (I have another with install ISO images, windows, kolibrios, and several versions of Linux.) I do not carry BSD, but this comment appears on the page of tested images Were I you, I would give it a try.
The page is here: http://www.easy2boot.com
note, if you are starting from linux or bsd, there is a page for installing E2B from such an environment. The main install page is for Windows users, since they seem to need more help.

I don't recommend it. This dates from 2014, and would not be representative of an up-to-date, modern, supported release.

A little history, at least for this particular BSD:

About seven or eight years ago, it became possible -- and relatively easy -- to install OpenBSD directly onto a USB storage device and then boot from it. So the value of downloadable "live" OpenBSD systems became less and less useful.

I should know. I used to build them for public download, with a variety of desktop window managers. But the last "live" media build I did was in 2011, because installing onto a USB stick became a standard practice, and the "live media" builds eventually lost their value.

I respond to myself !

https://sourceforge.net/projects/freebsd-gnome-livecd/

And more: http://livecdlist.com/os/bsd

You might like to have a look at this project - http://www.ghostbsd.org/