You could take questions from an actual copy of Trivial Pursuit.
Rewording the question and replacing the wrong answers might be good if you do that.
You could also flip the strip aspect of the game to be a reward instead of a punishment.
This of course can be easily circumvented by using google.
You could also flip around the decision.
So the reader chooses from 3 to 5 questions. (You could also remove the used question and add 3 new questions each round. If the opponent has answered more questions wrong, the ratio of opponent-friendly questions will be higher. And the other way around if the opponent has answered more questions wrong. You could also swap the outcome of some questions during the game. E.g. the opponent might be too nervous to get certain questions right after their tits are out.)
The opponent has to answer the question. If you dropped some hints about the opponent's strengths, the reader might use them to choose questions the opponent can't answer. Additionally, some surprisingly correct answers might lead to some interesting explanations from the opponent why they knew the answer.
The opponent's answer is wrong -> the opponent has to strip.
The opponent's answer is right -> the reader has to strip.
In a two player game, maybe replace pie pieces with this reward in order to balance the game's pace.
Pie pieces? Like you need to lose 3 tokens before you have to strip? In that case, it would also be possible to offer a different number of points for a piece of clothing. That way, you could also balance different sets of clothing. E.g. guy: briefs (4), pants (2), shirt (3); girl: panties (4), dress (5). It could also be used to give one of the players an advantage.
Don't use Monopoly. Nearly every aspect of the game is randomly determined - the occasional decisions you make have no real bearing on the outcome.
Without disagreeing with the other notes about Monopoly, I actually think it could be a good choice. (Though it doesn't rely on skills so it's not really a competition.)
A disadvantage could be that such games would be rather long. On the other hand, that makes it more difficult to cheat.
To make it easier and to avoid rule problems, you might want to use your own rules and a smaller board. (E.g. 4 fields per side and the edges for special fields.)
You would use predefined numbers for the dice rolls. So the rolls for player 1 would be 2, 5, 3, 6, 2, 1, and so on. Depending on possible events that are based on decisions, you should skip some of the numbers. This changes the order of fields the players will land on and makes it way harder to predict the overall outcome.
The structure should also be rather easy and you could work with many hub chapters. (Don't get me wrong... it will always be a lot of work to create a complex game!)
(E.g. you define the current field with a number variable "field_A" (A for player 1). The number goes from 1 to 20 as there are 20 fields. In the "Roll the dice" chapter you set the number variable "roll_A" to the roll and add the number to the variable "field_A". Then, have a link for every field from 1 to 20 (20 is the Go field where you might get double money). If "field_A" > 20, you add the respective money and subtract 20 from "field_A".)
It could also be an erotic game by default, so you could have Chance cards that tell the players to do some tasks like lapdances or sth. The order of these cards could always be the same. To change it, you could allow the player to cut the cards at the beginning of the game. The player who has to do the task will also change as some decision would lead to other players landing on the Chance field.
With game mode activated, it should even be possible to create a game board that shows the current position of the players on the board and even the number of hotels on each spot.
War has no random element at all. After the deck is shuffled and cut, you can already say who wins the game. (Only the order in which you put the cards back might make a difference but I think it's quite impossible to keep track of that on CHYOA with the current tools. I also think it will be quite boring.)
Depending on the number of dice, it might be quite complex.
Might be quite complicated as there are 62 potential zones one could aim for. And each zone might give you 10 or so fields you could hit. 301 to zero might work well for such a game as you could use some strategy.
Blackjack might be possible if the reader isn't the dealer.
You could define the cut (e.g. "a few cards from the top", "half of the deck", ...) and use a few decks.
The structure might be quite easy. (Changing the rules to remove the 11 or 1 option of the Ace might be good.)
If you don't bet and go for "lost game - strip" instead, the number of necessary decks and card chapters might be limited.
One deck should be worth 7 or more pieces of clothing. So if you create a set of two decks, it might be enough to get everyone naked. It might even possible for the reader to do card counting.
To add more randomness to Blackjack, you could add some unrelated decisions to occasionally skip a card or two.