https://xxxx.com/informe-calculadora/1/[email protected]&id=610
Redirect 301 /wp-content/plugins/custom-plugin/public/partials/informe.php /informe-calculadora/$1
The $1 “backreference” at the end of the target URL is in error (the Redirect directive does not support regex in which backreferences can be captured). This will likely be seen as literal text, which would explain the erroneous 1 at the end of the target URL (the $ is likely being filtered out).
The additional trailing slash could result if you have an additional rule that forces trailing slashes (either in .htaccess or WordPress)?
I had put it to collect the parameters but apart from being wrong it is not necessary.
Yes, any query string that is on the original request is passed through to the target by default. Unless you explicitly include a query string on the target URL.
However, since WordPress already uses mod_rewrite (for internally rewriting the request to the WP front-controller and other plugins are likely to do the same) then I would consider using mod_rewrite instead for this redirect, rather tan mod_alias (Redirect) in order to avoid potential conflicts.
For example:
RewriteRule ^wp-content/plugins/custom-plugin/public/partials/informe\.php$ /informe-calculadora/ [R=301,L]
This would need to go before the WP code block (ie. before the # BEGIN WordPress comment marker).
You will need to clear your browser cache before testing, since any erroneous 301 (permanent) redirects will have been cached by the browser. For this reason it is always advisable to test first with 302 (temporary) redirects.