don't be obvious with your approach. against what i consider the best jin on xbl (not that there are many, and not that this actually means much), that is how i play against him to go even or better.. still have to watch for their gimmicks though (ice resets, 6c guessing games [ib 6c->dp almost beats everything jin has at that point..] and cross ups/fake cross ups with j236d. 623d resets as well, you can just BK into fatal, gold burst, or dp out in those situations)
623b does not have invuln from frame 1, if he hits you with it you are timing your meaties wrong most likely.. if you are having problems with DPs on wake up/against jump ins, what you do is position yourself outside of forward roll range/throw range, os a 2a against quick tech and wait a bit right after they wake up before you actually start pressuring - don't be obvious with the bait and don't sacrifice your pressure entirely, this is what most people are guilty of when they try to bait a DP. if they start pressuring you on your wake up, you can probably try a quick 2a to attempt to catch their attempt to immediately pressure you next time, but it might take too long to recover and you might be hit by one of his DPs. anyway, if they start doing this in the first place you are being obvious with your bait/they guessed right.
depending on the range he used 236a you can probably punish it with 5b on ib. anyway, this match up is in ragna's favor slightly, i think. adjust to how they play.. if they can ib consistently don't throw out 2b 5c often.. if they bait your 6a/5a anti air with ice swords, beat it with a D DP on reaction or just run under and punish him.. if they mash 2a, fatal trap them with 2c. watch for their habits of using 6a as well (just watch for it from 2a/5a) and punish them hard if you can react & block it.