Yes, both Microsoft Power Automate and Nintex offer a Free Trial.
Microsoft Power Automate is designed for Medium Business and Small Business.
Nintex is designed for Large Enterprises, Medium Business and Small Business.
Pricing for Microsoft Power Automate Starts at $15/User/Month whereas for Nintex Starts at $1,405/Month.
Some top alternatives to Microsoft Power Automate includes Microsoft Power Apps, Nintex, K2, BP Logix BPMS, IBM Business Automation Workflow, UiPath RPA, IBM Robotic Process Automation, Built.io Flow and BPA Platform.
Some top alternatives to Nintex includes ProcessMaker, Microsoft Power Automate, K2, IBM Business Automation Workflow, Fusion Platform, ProcessPlan, ProcessPolicy.com, Bautomate, Withprocess.com and BPMapp by 500apps.