Here is some information from a preclinical study of creatine as an anticonvulsant published in Frontiers of Neuroscience journal in 2023:

- Potential role of creatine as an anticonvulsant agent: evidence from preclinical studies
https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2023.1201971/full
A key couple of sentences in the abstract for this publication are:

-Currently, limited evidence mainly from preclinical animal studies suggest anticonvulsant properties of creatine; however, the exact mechanism remain to be elucidated. Future work should involve larger clinical trials of creatine used as an add-on therapy, followed by large clinical trials of creatine as monotherapy.