As above, your best bet is probably to take a year out. You could then reapply to Oxford or Cambridge if you wish, and in the meantime also think about whether you want to do Japanese or Italian on the language side. If you do decide you're interested in the Japanese side, I can link some very informative comments about which unis to consider (and which perhaps to avoid) when looking at that! It would also allow you to avoid any hassle in trying to sort out accommodation at the last minute.
However in principle you can apply for almost any course through clearing, the point is though that not all courses are in clearing in any given year, and just because a course was or wasn't in clearing previously doesn't mean it will or won't be in future (the only reliable assumptions are that Oxbridge does not participate in clearing, and dentistry courses are unlikely to be in clearing as they normally operate waitlists). So Japanese at SOAS may be in clearing, and History and/or Italian at Exeter may be in clearing; equally, they may not be. There's no guarantee.