SMU is Special Make Up Unit. So, a product exclusive to that store, country or region.
That one goes across all brands. The rest of the terms are usually just made up by the marketing team/product team and are tailored to the brand.
e.g. When I was doing etnies bits, we had:
MT or HT - Mid Top or Hi Top.
XLT was a version of a shoe traditionally for everyday use which had been beefed up for skate standards.
The opposite was LS (Lifestyle, maybe?) which meant it wasn’t built to withstand skating.
There was another to denote it being waterproof.
They look absolutely mint, particularly in navy with brown trousers. Superb work. I was thinking they looked a bit Shoe Zone but you’ve changed my mind.
The starkest of contrasts to the pine green ones that’ve come out recently, which was the moment for me where the coin dropped on this shoe. This has just ripped them back into horrible again by association.