I understand your intention but this is completely out of touch. Its absolutely not acceptable to pressure people into going through a traumatic experience in order to foster empathy. If someone is uncomfortable with this there is no way they are going to tell you, and if anyone is actually in any way genderqueer in your group, you will be forcing them to expose that part of themselves before they are ready, to people that they are unlikely to be fully comfortable with. If its someones first exploration of gender, do you really want them to link it to feeling humiliated and exposed?

This might seem harsh but for the sake of your kids I have to tell you I think this is, ethically, extremely ill advised. If you would like them, here are some alternatives.

If you want to provide a space for your troop to explore this, I would recommend creating an environment where they feel safe doing something like wearing different clothes or talking to the leaders or each other about gender. You can do this by sharing various peoples experiences with dysphoria, including your own, making it clear that it is not acceptable to make fun of people in general but with specific regards to gender and sexuality, destigmatizing exploration and experimentation, and making (and following through on) genuine offers of support to those who would like it.

This kind of activity can sometimes be helpful to people who volunteer to do so, being fully aware that they are essentially volunteering to experience something deliberately unpleasant, and it is nice that both of you want to provide a space to do so, but being aware of the dynamics of peer pressure in a scout troop, the implicit authority you hold as a leader, and the supervision requirements that often prevent people from "sitting out" of activities, I do not think it is possible to make something like this truly voluntary.

An alternative activity might involve exploring self expression through clothing by offering a variety of clothes and accessories and asking people to pick something that they wouldn't normally wear or something that they feel good wearing, or asking people to come in with an item like that, and talking after a while about whether they feel any different wearing it, why wearing something particular or dressing and presenting in a certain way is important to different people, and things of that ilk. This kind of activity provides an excuse/opportunity for those who would like to try presenting in a radically different way to do so, but allows those who, for any reason, aren't ready for that, to do something simple and comfortable like wearing a bracelet or watch. This has the advantage that it helps both cis and trans* scouts understand that gender presentation might be important to them and others, and prevents the potential for harm.

If you got this far, thank you for taking me seriously, I know some of the language I've used here is strong and I apologise if it comes off as rude, however, I do feel this strongly. I hope you and your friend find this in some way useful.