We just published a build of MySQL 8.0.5 community server on yum.oracle.com, In the ARM64 "latest" repo.
We released an Oracle Linux 7.4 based preview for ARM64 servers a little while ago. See the announcement here.
A publicly available free download. No auth or access keys.
Once you have OL7.4 preview installed, you can get MySQL 8 going using the usual yum commands.
# yum install mysql-community-server