Increasing WAL Segment Size?
You can choose a WAL segment size with initdb when you create a new cluster. So you would have to dump and restore the data, which means down time. Jeff Janes' answer explains that this can also be done with pg_resetwal.

The only disadvantage of a larger WAL segment size I can think of is that the amount of WAL you lose when the file system with pg_wal on it is lost will increase. But that is a small problem and can be worked around with pg_receivewal.

I cannot think of a reason to change max_wal_size or min_wal_size because of a different WAL segment size, but perhaps a value of wal_buffers that matches the segment size would be beneficial.