Oracle 18c

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create table employee (name varchar2(30));
BEGIN
insert into employee values ('kevin durant');
insert into employee values ('michael JoRdaN');
insert into employee values (' dWyaNe WAdE');
insert into employee values ('james Harden');
insert into employee values ('pAuL ThomaS AnDersoN');
END;
/
1 rows affected

SELECT REGEXP_REPLACE(
         REGEXP_REPLACE(
           INITCAP(TRIM(name)),
           '(\S)\S*\s+',
           '\1.'
         ),
         '(.*\.)(.+)',
         '\2 \1'
       ) AS Name
FROM   employee


NAME


Durant K.

Jordan M.

Wade D.

Harden J.

Anderson P.T.