Galaxies Edge takes place 25 years after the Mandalorian. Based on his age and the rough timeframe of the Clone Wars he's probably in his mid-late 30's in the show. He'll therefore be about 60 in Galaxie's Edge... which is hardly a problem for a completely costumed character. Of course assuming he is completely humanoid-equivalent.
Baby Yoda at the age of 50 has the language milestones of a 12-14 month old human child, but his comprehension seems a bit out of keeping. His mobility puts him more around 18-24 months.
He'd therefore be represented as a 2-3 year old (25 years later). Hardly a shocking change for that character to be included either.
All hail toddler yoda.