Suggestions for Underlin

The following packages have something in common with the package Underlin. The packages are ordered in decreasing similarity.

Package scrlayer-scrpage: Define and manage page styles
Package scrlayer-fancyhdr: Combining fancyhdr with KOMA-Script’s scrlayer
Package clrdblpg: Control pagestyle of pages left blank by \cleardoublepage
Package chifoot: Chicago-style footnote formatting
Package fancyheadings: Legacy headings package
Package nccfancyhdr: Extensive control of page headers and footers
Package sfheaders: Sans headers
Package autofancyhdr: Automatically compute headlength for fancyhdr package
Package rplain: Redefines the plain pagestyle
Package scrlayer: Manage text layers within KOMA-Script
Package endheads: Running headers of the form Notes to pp.xx-yy
Package updatemarks: Extract and update marks from boxes
Package hackthefootline: Footline selection and configuration for LaTeX beamer’s standard themes
Package fancyhdr: Extensive control of page headers and footers in LaTeX2ε
Package floatpag: Different pagestyles on float pages
Package fwlw: Get first and last words of a page
Package titlesec: Select alternative section titles
Package titleps: Page style control
Package titlefoot: Add special material to footer of title page
Package continue: Prints continuation marks on pages of multipage documents
Package scrpage2: Control of page headers and footers in LaTeX
Package floatnohead: Suppress page headings on float-only pages
Package biihead: Underlined page headings
Package headerfooter: Define the layouts of page headers and footers
Package ushort: Shorter (and longer) underlines and underbars
Package umoline: Underline text allowing line breaking
Package uwa-letterhead: The letterhead of the University of Western Australia
Package handstroke: Eye-catching hand-drawn underline
Package arcs2: Arcs over and under text or math
Package koma-script: A bundle of versatile classes and packages
Package fancyhdrboxed: Elaborate page headers, specified in a non-LaTeX language