Luggage Issues on Shinkansen

I will be travelling from Tokyo to Shin-Osaka with Japan rail pass (ordinary) , my luggage is considered quite a big size . I'm wondering how can I bring it along with me during the journey ? I understand that JR regulations each piece of luggage may not weight more than 30kg and its three dimensions (length, width and depth) may not add up to more than 250cm, while its length may not exceed 200c but my luggage exceed the t&c .Is there any other options ? I'm thinking to use Takuhaibin , but I'm staying hostel(airbnb) instead of hotel , can I send to any stores to collect my luggage if I do so ?

No one actually checks luggage size, so unless it's so large as to arouse attention then it should be fine as long as you can fit it in the space behind the last row of seats in each car. Otherwise, consider shipping it via takuhaibin.

Btw, how are you gonna get your luggage on the plane? They are far more restrictive, and it sounds like you may be hit with some overage charges.