Sasha My concern, is that she may become aware of our dating rules and assume hers would be similar.
This isn’t even in consideration obviously, just something in my mind for potential future consideration
I'm not a parent, but I've spent a lot of time around parents and children in my life, and done a lot of babysitting. Here's my advice in case it helps.
Don't borrow trouble. Don't sit around worrying about what she might notice someday or what she might think someday. If she's not scared of you, she'll ask questions that will tell you what she's thinking.
When she does ask questions, answer them but don't tell her more than she needs to know at her age. These kinds of conversations can be revisited multiple times over the years in gradually increasing detail.
In this case, when she asks about the belts or dating rules, make it very clear in your answers that these are the rules that you chose for yourself and your mom chose for herself. No need to talk explicitly about dating rules for your sister before she asks, but you can plant the seed of the thought that you each chose what worked best for yourself, and you each adjust your choices as you learn more about what you need. By emphasizing the choice and individual needs when talking about yourselves, hopefully she won't get scared that you'll force something on her.
And do invite your mom to the forum!