My mom was the very first non-family member I came out to. There were a lot of happy tears from both of us. I was thrilled that I was finally taking steps to transition, and she was happy that she'd have a close female family member. We sat and talked like two old women for 4 or 5 hours, and she even shared a 40 or 50 year old family secret. She said it was something that a woman would only share with her closest friend. It made my heart nearly swell out of my chest when she said that.
I never had any doubt that my mom would accept me though. She was the very first person I knew who fully defended the LGBTQ community, and I knew she was going to be supportive. I'm really glad that your mom is so accepting too!! That will make things a lot easier for you.
I've read about a lot of your troubles with your wife, and this thing always comes to mind. If you started getting sick and the doctors discovered that you had some massive infection in your leg, I'm sure your wife would want them to give you medical attention. The may even have to operate on that leg, and amputate some of it right? Well you'd still be the exact same person after the surgery, you'd just be missing that part of your body. So you'd look a little bit different than you used to.
Well you suffer from gender dysphoria, which is a treatable medical issue. The only medical way to treat it though is to transition. You'll still be the same person you've always been, you'll just be healthier, happier, and look a little different. I would think your wife would be able to easily understand that.
(By the way I don't believe that transitioning goes against God at all. If she believes he created you, then that means this is what he wants for you. If she says that you're going against God...well maybe she's actually the one going against God by trying to stop you from becoming the person He made. Either that or she'd have to admit that God makes mistakes, and I understand that's a big no-no in most churches). That's my take on that.
Congrats on adding your mom to coming out list. I'm glad she's so supportive.