It appears that Botan versions since 2.2 (2.3.0 is the latest as of now), supports openssl-1.1 For example, I'm working to incorporate openssl-1.1 support into qca, but will probably have to disable the -botan plugin/backend until this is implemented.
See bug 1487067, there will be a botan2 package.
Thanks! I think I may even be able to help with sponsorship there, I'll take a closer look soon.
Package in rawhide (https://src.fedoraproject.org/rpms/botan2).
FYI, looks like botan2 hard-codes a bunch of it's own compiler/link flags, see: src/build-data/cc/gcc.txt (and throws away the distro default ones apparently)
sorry, I'll add that to the review bug
botan2-2.4.0-9.fc28 has been submitted as an update to Fedora 28. https://bodhi.fedoraproject.org/updates/FEDORA-2018-b2a764b252
botan2-2.4.0-9.fc28 has been pushed to the Fedora 28 testing repository. If problems still persist, please make note of it in this bug report. See https://fedoraproject.org/wiki/QA:Updates_Testing for instructions on how to install test updates. You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2018-b2a764b252
botan2-2.4.0-9.fc28 has been pushed to the Fedora 28 stable repository. If problems still persist, please make note of it in this bug report.