There is one way you can try:
1. First, move all the serial numbers to the end of each endnote (to ensure that the serial numbers can still correspond to the characters one by one after sorting).
2. Copy all the literature endnotes into the WORD table (the table can have only one cell).
3. Select all the contents in the table and make sure that each reference is on a separate line, that is, press enter later.
4. Click Table-Sort (Number of Paragraphs-Pinyin-Ascending or Descending)-OK;
5. Copy the sorted ones on paper and put the serial numbers back to the front one by one.
Note: Before copying the sorted endnotes into the paper, you may need to use the backspace key to delete them. The cut and del keys will not work, and you will be prompted that the operation is invalid. Moreover, a blank line will be left after deletion and cannot be deleted. If you want to delete those blank lines, you can only delete the endnotes in the article, which certainly does not meet your requirements.
However, if you want to change the labels in the original text, you can't automatically generate endnotes by inserting them, otherwise it will contradict your requirement of alphabetical arrangement, because WORD is arranged in the order of insertion.
If you want to achieve that function, you can only arrange the references in alphabetical order first, and then enter labels one by one in the article. In that case, the last number is likely to appear at the beginning of the article, which is not in line with the format of the paper. In a word, your request is a bit strange. It is completely two conflicting contradictions, which are difficult to solve.