yes, it's possible to create a new Trend that shows vCPU to pCPU ratio for Hosts. You can create a copy of existing "vCPU to Host cores ratio" trend and configure it to your needs, i.e.:
Then the trend lines should look like this:
Note: as this is a new trend, there's no historical data available. The trend process is executed automatically every 4 hours by default. It's recommended that the four hour period remains unchanged but if necessary it can be modified in Setup - Administration - Advanced Setup - System Properties -> "Hourly Interval for Trend Execution" property. You can also launch the trend process manually in Setup - Administration - Advanced Setup - System Maintenance -> Run Trends.
Does this trend suit your needs?