Emacs solo actually contains functionality for just that, the below snippet which allows exporting xref buffers to grep format by pressing 'E'. You can then use wgrep etc.
;; Makes any xref buffer "exportable" to a grep buffer with "E" so you can edit it with "e".
(defun emacs-solo/xref-to-grep-compilation ()
"Export the current Xref results to a grep-like buffer (Emacs 30+)."
(interactive)
(unless (derived-mode-p 'xref--xref-buffer-mode)
(user-error "Not in an Xref buffer"))
(let* ((items (and (boundp 'xref--fetcher)
(funcall xref--fetcher)))
(buf-name "*xref→grep*")
(grep-buf (get-buffer-create buf-name)))
(unless items
(user-error "No xref items found"))
(with-current-buffer grep-buf
(let ((inhibit-read-only t))
(erase-buffer)
(insert (format "-*- mode: grep; default-directory: %S -*-\n\n"
default-directory))
(dolist (item items)
(let* ((loc (xref-item-location item))
(file (xref-file-location-file loc))
(line (xref-file-location-line loc))
(summary (xref-item-summary item)))
(insert (format "%s:%d:%s\n" file line summary)))))
(grep-mode))
(pop-to-buffer grep-buf)))
(with-eval-after-load 'xref
(define-key xref--xref-buffer-mode-map (kbd "E")
#'emacs-solo/xref-to-grep-compilation))
