At even colder temps than that EV batteries start having even more problems, for example they become permanently damaged if charged at freezing temps or below, so even more energy has to be used to heat the batteries for the batteries to be able to accept a charge.
Easily mitigated by good charging practices (eg: charge when you finish a drive and the car/battery is still warm, not after leaving it in the cold overnight)
Yes, in very cold conditions, regen braking can be reduced/restricted until the battery warms up sufficiently. The car will warn you about this, so hopefully no surprises!
