You can talk to however many agents you like as long as you’re not signing an exclusivity agreement.

If you think there could be pocket listings your agent isn’t aware of, reach out to them and communicate that. Maybe they’ve already reached out to those agents, or they aren’t reaching out to who you think they should. The agents on both sides of the transaction want to find a buyer and seller, so your agent shouldn’t have any issues reaching out to agents outside her own group in order to find pocket listings. They gain nothing by keeping listings away from serious buyers.

Either way communication is key. You’re always better off going over these things with your agent to avoid and potential issues on your end. The last thing you want is to be on the hook for multiple commissions.