There is a lot of misinformation in the industry about car chargers. I can not recommend anybody but can query your need to have wall mounted charger. I apologise for the interspersion of US terminology and clarifications but this a US Forum.
The EVSE (electric vehicle supply equipment) control unit (the big box between the mains plug and the car plug on your granny charger) will not allow 240volts to the supply cable until it receives a signal from the car which operates a relay. That is all it does. The reason is safety... No live cable lying about when the car is not charging.
The granny charger draws about 12.5 amps which is just short of the maximum for a UK 13amp square pin socket. (The same current draw as a 3-bar elecric fire.) Unless your Leaf has the higher capacity 6.6kW onboard charger it will not charge any faster on an outdoor charger with the Menenkes type 2 socket. If your car does have the larger charger (it is available as a retrofit) or at a later date you do have a car with a higher capacity charger then a wall mounted EVSE charger connected to a dedicated fuseway on the consumer unit can deliver up to 32amps. For higher charge rates you are looking at a 3 phase supply.
There is a short and concise explanation here:- https://www.allaboutcircuits.com/techni ... -standard/
On a single UK 13A socket any electric car charges at about 10 miles of range for each hour on charge. If you think that is slow just think that in the US on 110 volts their granny charger only charges at 5 mph. So how many hours does your car stand around every day? So it is charging instead of just standing... So what? It makes no practical difference. (Apart from the trip hazard presented by the cable.)
Arranging weatherproof access for the granny charger or having an electrician install an outdoor socket would not cost much and even with a second EVSE would be a lot cheaper than a special charger... Which is basically just a wall mounted EVSE. All the people I know locally charge at home using a granny and that includes three Kias, another Leaf and a Tesla. Two run the cable out of the bottom of a sash window (seal the gap with a strip of foam rubber), one runs his out of the front door letter plate and the Tesla owner uses an extension lead down the garden path. One of the Kia owners lays the lead across the pavement! (US sidewalk.)
Although this may be irrelevent to you I would like to pass on a my personal experience of charging a small battery Leaf:-
I have had my 2011 24kW Leaf for five years next month. When I purchased the car I looked at a "white meter" (a timed dual tariff supply available in the UK) but rejected it. Charging on the cheap rate would have to be timed for a few hours each night but with a 3.3kW hour charger and a 24kW battery it would not often achieve a full charge in this time. Day time top-up charging "off-meter" would cost more and with the extra costs of installing the meter and the dual rate fees this negated any financial advantage to having the bulk of the charge on the white meter. I tend to be out in the morning and evening so regularly top-up for 2 or 3 hours in the middle of the day. (With the current energy cost crisis in the UK this may change!
I have relied on the original granny for home charging, as did the first owner. My car lives in the drive and the charging cable is lead from a dedicated 13A socket out of the garage via a notch I cut in the door frame. Effectively it is a tethered cable charger. No one has pinched it... Yet. But there are only a few feet of black cable visible from the road and I live in a quiet village. The socket is always switched on as the cable can not be live unless the car is charging. When not in use the charging plug it is hooked up out of the weather in an open bottomed box on the fence. When I get home it is a few seconds work to plug it in as I walk past on my way to the house door.
As a reassurance/backup I purchased a second granny off eBay (currently selling for £99 second hand to £159.99 new) and keep it in the satchel in the boot. I do not have to wrestle with a dirty wet cable in the boot and I am never caught out without a charging cable. I have never heard of a Nissan EVSE failing but even so it would be a pain if it did... The nearest public rapid charger is 12 miles away.
I also have a 30ft weatherproof extension lead which is useful for charging when away from home. I use it while dining at a car club meet, (the landlord is a car buff), and when visiting friends near the limit of the return range. I always offer to pay for the cost of the power used and it is a lot cheaper than using a public charger. I also have a Menenkes type 2 to type 1 lead for use on the slow chargers such as Instavolt and ChargeMyStreet which are much more common around where I live near Carlisle. (In Cumbria UK... Not Carlisle Philadelphia.) I tend to use it while shopping if the charge is a bit low or the local Geniepoint rapid charger has failed... Again.
One hours charge adds 10 miles which is enough to get me home in most circumstances.
Long journeys are do-able but take a bit of planning. I drove the car home from Diss (320 miles) and have driven it to Holland via Harwich in addition to a number of journeys requiring two rapid charges to complete.
Also it is wise to unplug the charger from the car on completion of charging. If you don't the detection circuit will stay live and draw down the 12volt battery. If you live in an area of poor 2G cover Carwings may cause battery charge problems. See my thread here:- viewtopic.php?t=33691
One last thought... Having a charging point will increase the value of the house; but it will be a bit of a waste of money if you go back to running juicer in one or two years time.
To sumarise it will be a lot cheaper to arrange weatherproof access for the granny. If a higher charging rate is important to you then a hard wired wall mounted outdoor charger is the way to go.
I hope this has been helpful to you.
Kindest regards, Emma