Question on position sizing for less liquid assets

Hey all, fairly new to the forum here but been trading for a couple years. Mostly focused on liquid FX pairs and some of the more active crypto, where getting in and out without slippage isn't usually a major concern, at least not for the size I'm running.

Lately I've been looking at some smaller cap altcoins and even some illiquid OTC equities, just as a way to diversify a bit. The issue I'm running into is how to properly size positions when liquidity is thin. I've read the standard advice about not taking a position larger than X% of your account, but that doesn't really account for the market depth. If my order itself moves the market significantly, or if I can't exit without massive slippage, that changes the effective risk dramatically. Do you guys use a different calculation or approach for sizing positions in these less liquid markets, or do you just cap your exposure at a much lower percentage relative to your usual highly liquid assets?