# [sed] -E, 69 bytes

    s/([FS][^FS]*){2}S/&s/;s/(B[^B]*){3}B/&w/;y/HX/wp/;s/[^wsp]*(.).*/\1/

[Try it online!][TIO-k95znjzs]

[sed]: https://www.gnu.org/software/sed/
[TIO-k95znjzs]: https://tio.run/##VY7BCoMwDIbvfRBRQcO2o7fAgvdcAp2eNsYuKnSjjOGrr0uql6Xwkfz9Ghpu1@Y@vVIKUHriwY@KuvocV4YiQKcx@hEtOq0IRYTuDb1AXOzOjzEsQ122VVvD5QApMbNj1OMQ0QbcJyZCspS120pNZtXQXMrMYHR7ztzbNntKO3KTVdveG0Q9sUhMFkd/JU62P@B3Xp6PeQqpOf8A "sed – Try It Online"

Input on stdin.

Output on stdout: w for walk, s for strikeout, p for in play.