I can't really give you that option within the release version of the simulator (other than maybe implementing different ones myself and just letting you select the one you want), but if you like, you can clone the source code from my Github and play around with that yourself. There's a Mutate method in the Evolution class that takes two parent chromosome strings and returns two offspring chromosomes, so that would be the only thing you'd have to change.
The project is not open-source - I'm currently not looking for collaborators and you can't redistribute the code so essentially all the regular copyright stuff applies - but feel free to experiment and play around with the code for any kind of personal or educational use! You can also send me an e-mail if you have problems with running the project or have any other questions. It might take a little while before I can answer because I'm a little busy at the moment, but I'll try to respond as quickly as I can. As a sidenote, I used Unity 2017.4.0 for the latest released version and haven't tested to see if anything is potentially broken in Unity 2018.2, so I'd recommend getting the 2017.4.0 version from the archives in case you want to edit the project.