Another attempt would be to use a regular expression.
This would include your 4th example with the leading year in brackets.
You could use the Convert Tag -> Tag (Alt+5) with a preview
Field: TITLE
Format string:
$regexp(%TITLE%,(.*)(\s\(.*remastered.*\)),$1)
Explanation:
Search and group together any character in TITLE until a space and an opening bracket is found.
Group together the space, the opening bracket and whatever is found before the word remastered and after the word remastered including the closing bracket.
$regexp: Leave only everything found before the opening bracket and the space (in the captured group $1) and delete everything else.
Of course you can also use the same format string in an Action "Replace with regular expression".
And as always for regular expressions: They are case-sensitive.
(The word Remastered would not be matched and therefore not replaced)
