I'm hoping to sell printable worksheets online for around $2 dollars each that are designed to reformat the character sheets that came with the base board game.
Where I believe I am adding value is by consolidating a number of sources of information together from the original game (rigid player cards, disposable character sheets) into one sheet that can reduce "table clutter" while including new elements also making it easier to (a) track one's progress over multiple game sessions, or (b) managing multiple playing groups (i.e. solo vs. groups of 4).
My main concern is that I am worried about infringing on trademarks or copyrights associated with the game.
On the sheets themselves, no original artwork is used; instead, I'm using icons that are identified as free for commercial use. In addition, the title of the game is not on the worksheet, so I'm hoping this does not give indication of it being an official product. I'm also planning on including some sort of footnote both on the document and in the listing for the product that this is not produced by the game publisher.
However, what does concern me is the inclusion of a quick-reference table that I've re-created into visual instructions rather than copying the words themselves.
Ultimately, I do believe my character sheet helps with the game experience while not altering it at all, but I do not want to be skirting the lines of copyright / trademark infringement.