It showed me “Plugin error from feature-classifier”
I am using the latest qiime2, version qiime2core/2018.11. q2-feature-classifier should be there. I did the same way with greengenes and it works fine, only problem with silva. Therefore, I supposed the q2-feature-classifier plugin should be fine.
Please show the complete error message. Re-run the command with the --verbose flag added and share the complete report here if it does not confirm what I suspect is the issue (see below).
Yes, sounds like feature classifier is working fine.
Without seeing the error, this almost certainly sounds like it is a memory error. Classifiers trained on SILVA take much more memory to use than those trained on Greengenes. Get the full error report as I described above, and if the report says that this is a memory error, see here for past advice on solving this system issue.