Chameleon pores and skin can be a freebie: it’s a passive means that grants advantage on Stealth Checks. No tactical implication; it just makes the yuan-ti better at what it now does.
These 3 variants all possess the https://crithitceramics.com/the-importance-of-setting-in-a-campaign-a-guide-for-yuan-ti-pureblood-monks/