Yes, both AMZ.One and Jungle Scout offer a Free Trial.
AMZ.One is designed for Large Enterprises, Medium Business and Small Business.
Jungle Scout is designed for Medium Business and Small Business.
Pricing for AMZ.One Starts at $15/Month when Billed Yearly whereas for Jungle Scout Starts at $19/Month when Billed Yearly.
Some top alternatives to AMZ.One includes Jungle Scout, RankActive, Outrankio, Sellics, K-meta Tool, Ranktracker, AMZ Alert, AMZInsight, AMZRank and Semrush E-Commerce Apps (Sellzone).
Some top alternatives to Jungle Scout includes Sellics, AMZ.One, Marketplace Manager, AMZScout, AMZ Alert, AMZInsight, Helium 10, Optiseller, ProfitGuru and AMZRank.