I do think it is possible to sleep train a EBF baby, having done it myself, twice
eats all. The.time she is hungry every 30 mins sometimes and she feeds on demand.
I don't think it's possible that she could in fact be hungry every 30 minutes. I mean, could you if you'd just eaten your lunch? Logically, if she's had a proper feed, then she won't be. There's something else going on here, she's got into the habit of snacking, she wants to comfort suck, she wants a snuggle, or something else. Does she have any trouble latching?
Like MJ&N, I would want to know how old she is and how long she feeds for. Are you offering both breasts for each feed? I would try to look for her different signs - tiredness, need for a new activity, and hunger.
Unless she's a teeny preemie, she should be able to go a minimum of 1.5-2 hours between feeds. Many babies from 6 weeks or older (and often younger) can do 3 hours, and many 4 mos and older babies can go 4 hours. Since you mention being worried about her being hungry at BT, I should mention that many people cluster feed in the evening (so two feeds very close together say at 5.30/6 and then 7/7.15)), and then dreamfeed around 10/10.30.
You must be feeling pretty tired if she's feeding that often!