I need to go to haneda from kyoto.
I have a medium size luggage.
I was thinking to stop at shin yokohama put my bag in a locker and go see some attraction in yokohama and then take a limousine to haneda.
the Shinkansen counter recommended shinagawa but did not provide the reason.
Is my plan doable? or it is better just to travel through shinagawa.
It’s possible, but keep in mind that Shin Yokohama Station is basically in the middle of nowhere. It’s a 30 minute train ride from there into the interesting part of Yokohama. It’s only 35 minutes by train from Shinagawa to the same area.
If you’re going to depart from Yokohama, I’d jump on the Keikyu Line from Yokohama Station rather than the extremely slow Limousine Bus. Unless you are planning to take an actual stretched limousine to the airport? 
but i will get to see shin yokohama ramen museum 
thank u for ur reply
There’s a subway running from Shin-Yokohama to Kannai and other parts of Yokohama.
If you can comfortable with Japanese, can take the Keikyu Airport Express train from Yokohama. Trains in Japan is far on time than buses. There’s many Keikyu trains going to different places so it may be difficult to get on the right train without being able to read the sign.
https://norikae.keikyu.co.jp/transit/norikae/T5?USR=PC&slCode=250-25&rsf=���l&SJ=0&tFlg=0&dw=1&d=1