Need JP Rail Pass? Osaka-Nagoya-Fuji-Tokyo

Hi!
Please help me out here. I'm overwhelmed by the information and still not getting the answer I want.
I will visit Japan March 1, 2019 - March 14, 2019. Here's my itinerary and please oh please let me know whether I would need JP Rail Pass or maybe other regional passes? (I checked Hyperdia and even with Hyperdia I confused which train uses the pass and which doesn't.)

March 1: Arrive in Osaka. Check in Hotel at Nagata
March 1: Nagata -> Osaka Aquarium Kaiyukan -> Namba
March 2: Nagata -> Universal Studio -> Shinsekai
March 3: Nagata -> Kyoto
March 4: Nagata -> Nagoya -> Fushimi Station (check in hotel near station)
March 5: Fushimi Station -> Legoland (Kinjofuto Station) ->Nagashima (see Nabana No Sato) -> Fushimi Station
March 6: Fushimi Station -> Shirakawago -> Fushimi Station
March 7: Fushimi Station -> Fujitan Station
March 8: Fujitan Station -> Fujiten Snow
March 9: Fujitan Station -> Hakone
March 10: Fujitan -> Ningyocho Station (check in Hotel)
March 11: Ningyocho Station -> Disneyland
March 12: Ningyocho Station -> Disneysea
March 13: -
March 14: Ningyocho Station -> Tokyo Narita Airport

Any advice greatly appreciated!

TIA

Read the "How to use Hyperdia" section on this website, and also use the rail pass calculator in the transport section.

Not even close - a basic one-way trip between Osaka and Tokyo is half the cost of the national pass (not even counting the non-JR trains you are taking.)

I guess you mean Nagata on Osaka subway/Kintetsu station. You may consider Kintetsu rail pass.

https://www.kintetsu.co.jp/foreign/english/ticket/krp.html

With this pass you can go to Kyoto, Nagoya, and from Nagoya (Kintetsu Nagoya) to Kintetsu Nagashima (Nabana no Sato).

The Kintetsu Rail Pass does not cover Osaka Subway, Nagoya Subway or Nansai (from KIX to Namba) so you should buy ICOCA at Kansai Airport. Yokoto Osaka ticket is a good option.
https://www.howto-osaka.com/en/ticket/ticket/yokoso.html

From Nagoya to Shirakawago, the cheapest way is bus.

http://www.gifubus.co.jp/highway/shirakawa/

See "Timetable and Fare (English)".

If you can cancel the hotel for your last night in Nagoya and stay Takayama instead, go from Shirakawago to Takayama and take bus from Takayama to Fujisan (or Kawaguchiko).

http://bus-en.fujikyu.co.jp/highway/detail/id/38