Er... you\'re getting really baffled here, let me sort you out.
YES YOU CAN DO THAT.
There are a million reasons why you can and absolutley NONE why you can\'t.
Anything else is a pointless discussion about fluff (though see below).
As far as rules go, the following applies \"This female, dressed in space marine armour \'counts as\' an Emperors Champion\" mkay?
End of story.
Glad I could clear that up for you all...
Resorting to the Witchhunters Codex, women serve the Emporor because they are uncorruptable like men (dont know why, its the fluff) The SoB have whipped out several chapters throughout history causing sever distrust in other chapters.
Where on earth did you get this? I have never read anything like this in over 20 years of GW fluff reading. I guess I might have missed it int he codex, I\'ll go have a look tonight.
OK firstly in RT there were female space marines, I have the 2 minis they made.
Later marine chapters have been all male (I can\'t actually think of a single female marine in any of the the later fluff, but I\'ve not read everything).
SoB are NOT marines, they are not genetically enhanced in anyway, just highly trained and devout warriors. The reason they are used as the warrior arm of the eccelisarchy is because of the ban on them having male warriors, its a literal interpretation of a law that was supposed to make it impossible for the eccellisarchy to have warriors.
Within the fluff, it would be reasonable to assume any of the following:
1) Women can\'t be made into marines for genetic reasons.
2) Women can be made into marines, but aren\'t due to religous/superstitous/law reasons.
3) Women can and are made into space marines, just not as often as men.
Yes these are contradictory, but then a lot of 40K fluff is.
The bottom line is that you can do whatever you want. I could use a robot as an emperors champion, or a giant fluffy rabbit if I really wanted. As long as my opponent knew that it was an emerors champion and it wasn\'t too confusing for him it would all be fine and legal even in a tournament.
If anyone complained, then I suggest you submit them for mind scrubbing for being sad useless individuals that need to get over themselves and get a life.