The first thing to note is that ebikes are bicycles. Generally, you don’t need special tyres for ebikes. But because you have the assistance, you can tolerate special tyres that are a bit heavier and give you puncture protection. That’s a really good thing for commuting! For eMTB, that means you can go wider, 2.6″ or 2.8″ being de rigeur. I have had a few sets of Schwalbe tyres of various persuations and been satisfied with them. Not all are available in all diameters and widths, so check Schwalbe’s website for availability. My advice is to go as wide as you can (at least 37c), and as puncture-resistant as you can. If you are confused about wheel size, there are 4 main diameters, and within stick to near the width your bike came with. Widths might be in mm or inches (37c being 37mm wide, or 1.5″; 42c is 1.75″; 50c is 2.00″; 60c is 2.35″)
20″ – most folding bikes have 20″ rims
26″ – is what older mountain bikes and many Chinese-sourced bikes have
27.5″ aka 650b – most common with newer eMTB, less so with other ebikes (some Smartmotions including Pacer have this size)
29″ aka 28″ aka 700c – most common on commuter ebikes. Yes, you read right. 28″ and 29″ are exactly the same size (it’s measured to the outside of the tyre, so a MTB tyre on a 700c rim is ~29″ whereas a road tyre on the same rim is ~28″)
If you are looking for performance, you can check out the rolling resistance site which also measures puncture protection (in a lab though, not the real world). Being a nerd, I went straight for Schwalbe Almotion and set them up tubeless. They are very nice. Once you have found your ideal tyres, you can go to your local bike store and try to buy some. Good luck! Sadly, many NZ shops have a very limited range of tyres suited to ebikes, or touring bikes in general. Try a specialist ebike or touring bike shop too. IF you have no luck, try an offshore online shop including Chain Reaction, Wiggle, Amazon or Bike24, all of which (typically) ship to NZ for not much more than local retailers. [The Chain Reaction link is an affiliate link which helps me by maybe paying a small commission] Some other considerations:
If you want to run your wheels tubeless, buy tubeless ready tyres. There is a learning curve to tubeless so it’s not for the faint-hearted.
Softer compounds and carcasses give better grip and comfort, but at the expense of wear. You’ll still get >5000km from soft touring tyres on the road, 10,000 for harder compounds.
Pattern means very little with road tyres, even in the wet. Compound is more important.
All brands have average, good and great tyres in their line up. Even within one model you can get different versions.
Feel free to ignore the e25 and e50 ratings. It’s just a rating made up by some guy with a clipboard and means little in the real world.