>>44737545Well technically a Pokemon could vary in size, they are not limited to their averages. Pokemon Lets Go and Eevee establish that Pokemon can have an upper limit of +/-40% their natural height and upwards to +/-60% in weight.
So a Swampert could max at: 6'8 and 252.6 lbs. Using that games metric. It could probably be higher, but as far as I know thats the limit.