At Christmas and Easter, the last couple of parishes I’ve attended have had a penance service, where several priests from other parishes in addition to the parish priests hear confession. The will often set up a temporary confessional that consists of a portable “wall” with a screen and a kneeler for the penitent, a chair for the priest (on the other side of the screen), and a chair for anyone who chooses face to face. this is set up somewhere in the church, often in front of the altar, completely in the open. And those wishing to use, stand in line at least 20 feet or so behind the “confessional” After the penance service, this “confessional” is taken down and stored in a closet.
Seems like if they did that for all confessions, 52 weeks a year, it would solve the problem, and do it cheaply. Besides, what abuser would dare try something with a dozen or so people “witnessing” the confession from 20 to 30 feet away? Seems simple to me.
Besides, going to confession right in front of the altar sure would make me think a bit harder about what I was saying. Especially under the giant crucifix hanging above said altar.