Yes, the freeware version of Lansweeper only supports scanning with the LsClient scanning method: http://www.lansweeper.com/kb/7/how-to-scan.html
No other scanning methods are supported in freeware mode.
Also important to note about the freeware version of Lansweeper:
• Supports just one domain/workgroup
• No VMware or Hyper-V host scanning
• No SQL Server scanning
• No warranty scanning
• No hardware or software history tracking
• No (software or OS) product key scanning
• No access to the report builder
• No active directory integration
• No report/event log email alerts
• No access to technical support