Mistwell
Crusty Old Meatwad
Sure there is, a Lizardfolk Monk that is proficient in shields can just keep a shield on their back, (not wearing Heavy armor).
If Scales and Shield would yield a better AC, the Monk equips the shield. If the monk needs to hit nitrous..the monk drops the shield.
If Plate Armor..say for a battlefield sequence would be a better option...it is an available option as well.
If Magic Loot is found that changes the balance of the numbers, you adapt your style to make use of what is available.
The part in italics is a brief summation of Musashi's fighting philosophy....Mr. Kensai himself.
OK I see what you're saying now. I thought you were saying there was a good option for just Lizardfolk natural armor. I see you tied it to a shield so yes that does make sense.