Yes, both Slack and Metaplane offer a Free Trial.
Slack is designed for Freelancers, Large Enterprises, Medium Business and Small Business.
Metaplane is designed for Large Enterprises, Medium Business and Small Business.
Pricing for Slack Starts at $2.67/Month whereas for Metaplane Starts at $208.33/Month when Billed Yearly.
Some top alternatives to Slack includes Microsoft Teams, Glip, Google Chat, ChatWork, Dialog, Office Chat, imBee, Takle, SPACE Channel and Teamwork Chat.
Some top alternatives to Metaplane includes Celonis, Qualified, Grai, Workvivo, Mojro Executewyse, Datos Intelligence, Blue Yonder Warehouse Management, Supertrace, ClearMetal, IFTTT and Online Check Writer.