Catalina
The tokend technology is deprecated since macOS Lion (10.7 in 2011). With macOS Catalina (10.15 in 2019) the support of tokend is disabled by default. But Apple provides a way to enable it again.See my previous article "macOS Catalina and smart cards status".
Catalina, first minor update
With the first minor update of Catalina (10.15.1) the support of tokend seems to be broken (not just disabled).I reported the problem to Apple (feedback FB7455638) but have no news since then.
You can also report the same problem to Apple to give the issue a higher priority.
My recommendations
If you depend on a working tokend support then do not upgrade to Catalina and stay with Mojave (for now).While in Mojave migrate from tokend to a CryptoTokenKit plugin equivalent. The CryptoTokenKit plugin is the new technology introduced (in macOS Sierra 10.12 in 2016 "macOS Sierra: Smart Card Driver Extensions") to replace tokend.
Once your CTK plugin configuration is working fine you can migrate to Catalina.