My plan. Will this work or are there better options?

We recently bought a 2015 Nissan leaf S with charger pack.

My current plan is to get a evse upgrade so that the evse that came with car will be upgraded from 110V to 220V
After that I'm planning to plug it in a 220V outlet (currently there is no outlet in our garage and we need to get one). However I'm not clear about certain things.

The website where I can order the upgrade sells a bunch of adapters and I'm not sure if I have to order an adapter as well.
When we get a 220V outlet installed what kind of outlet should it be(like the specifications). Can I directly plug the evse into it?

With all of these in place and a 6kwh on board charger, how long will it take to fully charge the car from 0 to 100% ?

EVSEUpgrade can be a great option. However, since you're already paying to have a cable run and outlet installed, you might want to consider a wall mounted, direct wire unit. Home Depot has a Schneider EV Link unit that gets good reviews on sale for $499 ($100 off with code EVLINKSUMMER). That unit will allow you to charge at the full 27.5 amp rate that will get you the fastest charge. It's not a huge difference from the 20 amp charging you'll get from the EVSEUpgrade, but you mentioned speed, so that may be a factor to consider.

You will need an adaptor to go from the EVSE Upgrade to a regular 120 volt wall outlet. Other adapters are available for things like dryer outlets and RV parks, just depends on where else you might charge up.

For the outlet, EVSE upgrade uses a high quality NEMA L6-30 locking plug. It will require the appropriate wire size and breaker capacity as determined by your local code. You can search on here for some examples of folks that have installed them and what materials were used.

The gentleman behind the EVSE Upgrade, Ingineer, is active on this board. You can find threads with lots of details on the units with the search feature.

What you need to do is figure out what plug is on the upgraded EVSE, and get the same type receptacle installed in your garage.

The adapters are for when you are out and find a 240V outlet that does not match the one you use at home. It might be nice to get the 120V adapter, as those are a lot more common.

When I had my 240V receptacle installed, I had them run a separate 120V line to the same place so I could use it as a backup in case the 240V EVSE failed.

(I have not had to use it yet, in fact there is an air compressor plugged in to it that does get some use, what with all the screws I've picked up.)

After converting your EVSE, you will not have that backup option though. Getting a dedicated EVSE will be faster than the upgraded Nissan one, and you can get them both to plug into the same outlet if you want, so your backup would at least be 240V. (I used a 6-50 receptacle that I had already.)

It sounds like you are on the right track. I had a 14-50 installed in my garage and got the 'universal' adapter from EVSEupgrade and am very happy. Likely I "Could" have had the L6-30 installed but I wanted maximum future use of the plug and the adapter I received is very heavy duty/solid so I have no concerns about using it on a regular basis.

I am in the "for home charging the nominal benefit of a wall-mount is of little additional value" camp. Yes, wall mount could charge a tad faster, but my usage pattern won't appreciate the difference. I just don't see myself driving the battery down, then charging mid-day to then head out and need 100% charge to make it through the day. Going from the 120v/10a to the 240v/?a that ESVEupgrade did was enough of a boost to make my day.

Now if there ever was a cheap DCQC for home use (ha!) that could do the 30 minute to 80% charge that would be noticeable.

EVSEUpgrade uses a 'NEMA L6-30' plug so you need a matching outlet connector if you prefer to avoid adapters.
Generally this will require 10/2 wire and a double pole 240 volt breaker.
Upgrade and use adapters if you like.... I recommend just getting what you need.

the nice thing about going L6-30 is it's not all that big, and can be installed in a regular sized box, and you don't have to worry about the plug coming undone. If your wire run is easy, like most houses with the panel in the garage, just go with what you need, and if you ever need a bigger plug later, you can install it then.