This is a normal behaviour of gui flavours of vim like gvim.
é are the same thing.
Usually people aren't bothered by meta+key inserting an accentuated character, but the other way around. See the very old issue with French people needing to insert
é in LaTeX document which in turn triggers
\item insertion (IIRC) with vim-latex.
My opinion on the subject: don't bother with it and learn not to type
PS: while I was looking for the recent discussion I've seen in my mailbox on this topic, I've found the vim issue # 5644 that OP has probably initiated (given the timestamps). Why is this question active today?