I often use to edit my manuscripts because it is cool for inserting equations. The other reason is that I can only focus on content and keep away from the typesetting.
Recently, one of my paper had been accepted and a final version should be submitted before proofreading. However, this journal asked me to follow the British spelling and I have no idea how to complete this work as soon as possible. Thanks google again! This task can be done easily by WinEdt, which is my most familiar editor for typing tex file.
My version is WinEdt 9.0, but I think it is not an issue. First, find Tools in toolbar and select Check Word, the following dialog will pop out:
Then click on Dictionary Manager.
There are a few dictionaries enabled for checking word, and what you need to do is to disable those for US spelling (e.g., English (maximize), English (center)).