There is rarely a good reason to change fieldnames because they are never really exposed to the user in a good design. You can change label captions on forms and reports instead. It is rarely worth the effort unless it is very early in the project.
If NameAutoCorrect is enabled, references to the fields in Queries, Forms and Reports will be changed the next time they are opened.
References in VBA code, SQL strings in the RecordSource and RowSource properties won't be changed automatically.
However occasionally NameAutoCorrect can cause corruption that can be hard to fix. You will need to thoroughly test everything, and I mean EVERYTHING in the project.
If you really want to go ahead then download V-tools and use its Total Deep Search to find all references to the fieldname in the project.