Steroid weight gain (for professional fighters) is mostly water weight which is relatively easy to shed for the weigh in (I referenced Canelo just now, he routinely sheds 15-20 pounds and regains it within the span of 24 hours for his fights, because it's all water weight, he doesn't have to lose fat or muscle to do so). Beyond that steroids simply help you recover better and build muscle easier, but you still need to put in the work, and you can't get bigger on a caloric deficit no matter how many steroids you use. So steroids for fighters aren't commonly associated with weight issues (they do outside of fighting, for hormone treatments or bodybuilders).

Beyond that I don't know if Cyborg's on steroids, I don't follow her much and I wouldn't be surprised if she was, but I don't see her weight as being remotely related. Again, it's extremely untypical to go down in weight classes, if that was supposedly indicative of steroids I can literally name a hundred fighters who'd be suspicious from the top of my head.

Anyway yeah she said it a couple times that she could do 135, yet it hasn't happened because she wants the fight at 140 at a catchweight I suggested (I'm just reading this now). I mean Cyborg just a few years ago won gold medals at at 74kg or 163 pounds. Now she has to drop down to 135 pounds from there, or 10 pounds from her 145 fights this year? Instead of Ronda agreeing to go up 5 pounds to 140, when Ronda competed just fine in tougher competitions at 154 before? So supposedly she's got the self confidence to fight anyone, to beat men, to even beat elite female boxers like Laila Ali IN BOXING, when Laila competed up to 175 (I mean it's just a total joke), yet Ronda doesn't want to go up 5 pounds for Cyborg to go down 5 pounds and make the fight happen?

Cyborg has been suspended in the past for steroids usage. Steroids are directly related to muscle gain and that's Ronda's point:

http://www.sbnation.com/2015/8/2/9086623/ronda-rousey-challe...