Female agents ought not discriminate against male writers of romance. And maybe they don't. I tend to find the agents most likely to be interested in my thing, which is not romance, are male, based on their stated wish lists. It's under consideration again with a male agent who saw it before and suggested the story didn't start in the right place, but said he really, really liked the voice.
What may work against me as a female writer, is exactly that. The voice. I have written this novel first person from the POV of a male police officer.
I originally wrote the whole thing third person, but turning it first person was so freeing. This agent says it is a brave thing to do. Which could translate as 'mistake.' Risky.
My bad? Gender appropriation? It could backfire, though I could easily turn it third person again.
Michelle Paver does it.
@AgentPete's client. Writes first person male. Humanity first. I know men, why can't I write male, and vice versa. I am so sick of identity politics I could puke. It's toxic, turning evil actually.
The muse should be all that counts. And for the agent, the market. It works or it doesn't, it's the agent's cup of tea and they know how to flog it, or it isn't and they don't. I'd just focus on the individual agent Steve, what they say, how they say it, see if you detect a possible fit on that basis. If they're not prejudiced, you shouldn't need a pseudonym. If they are, well, you'd need to reveal your identity at some point should they take it.
For the writer, we can only worry about the writing. That's plenty to be worrying about, and if we can get that right, and it's damn hard, sooner or later, it should find the light of day.