Yes, there is a difference between the two at the configuration level.
Let's look at Standalone and Pseudo distributed mode one by one.
Single Node (Local Mode or Standalone Mode)
Standalone mode is the default mode in which Hadoop run. Standalone mode is mainly used for debugging where you don’t really use HDFS.
You can use input and output both as a local file system in standalone mode.
You also don’t need to do any custom configuration in the files- mapred-site.xml, core-site.xml, hdfs-site.xml.
Standalone mode is usually the fastest Hadoop modes as it uses the local file system for all the input and output.
The pseudo-distributed mode is also known as a single-node cluster where both NameNode and DataNode will reside on the same machine.
In pseudo-distributed mode, all the Hadoop daemons will be running on a single node. Such configuration is mainly used while testing when we don’t need to think about the resources and other users sharing the resource.
In this architecture, a separate JVM is spawned for every Hadoop components as they could communicate across network sockets, effectively producing a fully functioning and optimized mini-cluster on a single host.
So, in case of this mode, changes in configuration files will be required for all the three files- mapred-site.xml, core-site.xml, hdfs-site.xml.
Hope this will clear the difference between the two modes.