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I searched "hiring a rival" and came up with *Corporate Warfare (when companies take the metaphor of "being warriors in business" literally)
- Rival Science Teams (when scientists compete to reach a goal or discovery first, or freelance to anyone willing to pay them.)
Not sure about getting a good person to work for you instead of another company or group. "Headhunting" is the real-life slang term for this.
Seems like Corporate Defector would be a good trope name for this phenomenon but I don't see anything about it on Betrayal Tropes that's specific to getting poached.
Related would be The Corruptible, Mistreatment-Induced Betrayal, or The Mutiny
Edited by Jetbent 60% of the time I work every time

One group/organization, can be a business/team/warrior group/whatever, recruits a quality member of their rival/enemy group/organization. Sort of like a "if you can't beat them, get them to join you" situation.
For example, in the The Office (US), after years of losing potential clients to rival paper company salesman Danny Cordray, Michael offers him a job to work as a traveling salesman for Dunder Mifflin.
I don't think it's Enemy Mine, since you aren't just temporarily teaming up but actually have them join you. I don't think it's Defeat Means Friendship, because the fact that you can't defeat them is the reason your having them join you. It's not Enemy Exchange Program since the rival organization isn't willingly giving them up.
Could definitely overlap with Heel–Face Turn, but they don't have to be "bad" first. Could also overlap with Sixth Ranger, but in this case, they are explicitly a member of a rival organization/group first. Your taking them away from that group is just as big of boon as you getting the new member.
Happens frequently in the Real Life business world, to the point where many company contracts have provisions explicitly preventing their employees from leaving to work for a rival for a set time period after.