They won’t slide off. Dealt with alot of subarus and never have had that happen ever, yet I HAVE seen braided lines fail at the hose end due to improper assembly procedure. If you’re going to replace them, just give Fred a shout at Capitalland 399-9900 and order up fresh oem lines and the associated clamps.
The do make compression -to- AN type fittings but it’s more of a hassle and you’re just creating another potential leak point. If you’re going to attach AN fittings to the hard lines, you’re better of removing the lines and brazing steel fittings directly to the lines to attach the hose ends/hose barbs for whatever line you’re going to run. the compression style fittings do work though, but the line must be perfect(no rust, coating, scratches, etc)