The best replacement for freemarker is velocity.

The best alternatives to freemarker are rated as following:
★★★★★  velocity
★★★★  jsp
★★  thymeleaf
★★  xslt
★★  mustache
★  jstl
★  sitemesh

Your alternative for freemarker is not listed? Suggest!
Speaking about freemarker, one probably shouldn't forget about spring mvc.

Other search terms related to freemarker and their ratings are:
★★★★★ spring mvc
You have in mind a companion for freemarker and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of freemarker in all years. Click on graph for more.
freemarker
velocity
jsp