Hey @Felix you should be able to change the command name in Rocket/Commands.config.xml file for example find the original ChallengeRewards command:
<Command Name="challenges" Enabled="false" Priority="Normal">RestoreMonarchy.ChallengeRewards.Commands.ChallengesCommand/challenges</Command>
then enable and rename it to quests
or missions
for example:
<Command Name="missions" Enabled="true" Priority="Normal">RestoreMonarchy.ChallengeRewards.Commands.ChallengesCommand/challenges</Command>