I suppose it depends on by how much, and what, things can be adjusted - and how easy it is to do so, but you should, at least, be able to lower the saddle. The weight of the things concerns me and is one of the reasons I didn't go for an e-bike when I returned to cycling last year (at the age of almost 75!). Also how easy it is to load will depend on the size and especially height of the car and how much space you need for everything else.
I'd be inclined to have a few dry-runs beforehand, cleaning everything out of the back, putting the back seat right down and covering it all with a large old sheet. See how easy it is to get in and out with and without help, different positions etc. You might find you can get it in easily enough but then need to reposition it; moving it by means of the sheet underneath is less likely to cause 'issues' (to bike or interior of the car) than dragging the bike itself around. If you can lower saddle and handlebars, you may be able to use a lightweight ramp to get it high enough up to be able to slant it and then ease it into the rear space.
Consider removing any 'extra weight' from the bike before trying to put it into the car, too - just don't forget to put eg the battery into the car, don't leave it behind! Take off any baskets etc too. I think getting it out might be even more awkward than getting it in , and having a sheet underneath it will really help to reposition it for easier and safer removal. So will an extra pair of hands!
Consider carrying a box of lightweight disposable gloves and/or some babywipes if you're going to need to ask people to help you get the bike in and out then they won't be getting their hands mucky. I have a packet of babywipes with me when I take my bike on trains as there's almost always someone who offers to help and I'd feel bad if they got greasy or marked by anything. It's useful for yourself, too, if you need to clean yourself up after tweaking something when out on a ride.
Have fun on your bike!