Re: 'Agile' means nothing at this point. Unless it means terrible software.
Then you spend weeks/months going back and forth between the business and technology teams with both sides hating you for just doing your job.
That just means you aren't actually doing your job. The whole thing about being a BA is being a Business Analyst which mean working out what are the actual problems and pain points of the business. Being a BA is NOT just passing on a solution that has been requested by a customer.
I am qualified as BA and have worked as a BA and the first thing you learn (if you don't you are an idiot) is that humans all ways define the problem in what they perceive as the solution.
A little example is the person who comes into the shop looking for a star shaped piece of glass to fix a broken window.
So instead of giving a set of requirements to the build team defining a star shaped piece of glass the actual requirements are "Replace Window" simple.
<End Trainer mode/>
If as a BA all you do is pass through what the client asks for then you deserve all the shit you cop.