No, and indeed, since you’re not going to be working as hard as you would on a normal bike, you can arrive at work not dripping with sweat. Everyday clothing is fine, although a good cycle specific jacket will help on those occasions when you need weather protection, and they tend to be brightly coloured and reflective. We do however prioritise reasonably bright clothing and choose to have the inbuilt bright bike mounted lights switched on both day and night, a la Volvo. Hi-Viz wear is optional, but recommended at night. Personally I rate endura kit highly – accurate sizing, good value and robust, and the offerings from decathlon are great for inexpensive moderate everyday wear.
Helmets: Being classed as a bicycle, helmet wearing is not mandatory on e-bikes, it is a matter of choice and is a judgement we personally make based on road and weather conditions. Our favourite is the super comfy and high value bontrager/solstice-mips-helmet
‘However good your saddle, if you are cycling any significant distance – say 5 miles or more – you will definitely benefit from wearing a pair of cycling specific shorts or undershorts, the ones with a bit of padding, and I recommend using a spot of Chamois cream, Nappy cream or Aqueous cream with them if riding regularly or far, and keeping right on top of hygiene, to keep the bugs at bay.