I’ll be the first to say I don’t have any backing from the Catechism on this

but it just sounds like a really, really bad idea, for the reasons BlestOne stated. The Protestant denominations seem to have pretty high standards and expectations for their pastors and their families. Nothing wrong with that at all, but I don’t think a congregation would be very happy with their pastor’s wife and kids being Catholic. They put a lot of emphasis on the husband’s “spiritual leadership.” From their POV, if a man can’t even lead his wife out of a “false church” how would he be able to lead his congregation properly? The only solution I could see would be the Catholic caving and going to her husband’s church. If I were a priest (and I’m not, mind you) I wouldn’t be minded to grant a dispensation if there was such a low likelihood of the Catholic maintaining their faith.
Now I’ve written all this assuming the Catholic was the wife and the pastor was the husband. Could definitely be the other way around, but I think there would still be the same concerns.