You don't need to mention stats or precise mechanics. "Stats as [monster name]" means you literally write just "stats as" plus the name of the monster. The folks reading it will pull the actual stats for that critter from the system of their choice when they run the hexcrawl. So if I wanted an encounter to be monster dogs, the list entry would read "pack of 1d10+10 Mutated Hounds (stats as Wolf)".