I think if you ate a whole loaf of soy and linseed bread (eg “Burgen”) every day you still wouldn’t achieve even slight feminisation, though I’m only speculating, and as Sandra says, such quantities may even have a toxic effect [not “intoxicated” Sandra my dear, that means drunk!]
By my calculations that would also be about 6 times more expensive than taking a low dose of estradiol, and perhaps 600 times less effective at feminisation. When I started taking hormones, 2mg estradiol per day cost me about £5 a month, not as expensive as you might think, cheaper than herbal-type hormone supplements or even plant oestrogen-rich foods, both of which will interfere with the effects of "real" HRT.
If you plan to transition when you're older, for the time being just stay healthy, eat well and avoid drink, drugs, smoking, anything that you know is bad for you. And don't leave it too long; a young healthy body will be much more receptive to the positive effects of HRT than an old knackered one!
Welcome to the site, Cathy.
xx