It used to be that you had to be on a 'connection' which is defined as less than 4 hours (and as an 'X' vs 'O' on the ticket) to get boarding passes.
Now, I understand you can get boarding passes that go for 24 hours from the TIME of your first checkin.
Flight #1 departs at 2pm, you land at 6pm .. stay the night and Flight #2 departs at 10am the next day. This should work.
I have done it all on AA so cannot say about OW carriers (and within 'normal' US time zones so cannot comment on Asia/Europe time zones).
I many times have taken a 6am flight out .. with an 11pm flight back (LAX-ORD-MSP). They can issue the BPs except that the final flight (ORD-MSP) leaves at like 7am the next morning so that is outside the 24 hour window.
OLCI .. hm .. not certain when the 24 starts on that since it is 24 before first flight .. may be only that the first flight will be allowed (or the 24 hour clock starts with that OLCI). I always use PERSON checkin at the airport. That might be the 'trick'.
Bags . again on AA should work (unless there is some wierd countries involved).