I cannot see this law being imposed, and no doubt the paper is spin doctoring. If a child molester honestly confesses, i.e. that he will not sin again, then I would assume the priest could advise him to turn himself in to the police. In any case, I would also assume that someone confessing such a crime would ensure they went to a parish , county, where they were not known - hence there is no way the priest could identify him, be that a lay person or another priest. The priest cannot apprehend the confessee and if he does not know his name, as Corki pointed out, there is no information he could give to the police anyhow.
Either way if the ‘law’ was enforced, how many child molesters will confess - NONE. They can go to confession in the UK, i.e. drive to Northern Ireland a few hours by car, or wherever this law has not been passed.
It’s all a load of nonsense if you ask me, it’s just another knock at the church by trying to infer the church still ‘covers-up’ and protects child abusers from all angles, and hence more dissent and mockery against the church.