Problem: In nearly every language wiki there is a system, to show a route diagram of the line/route. examples: nl:Spoorlijn Amsterdam - Elten (traject in the infobox), de:Bahnstrecke Amsterdam–Arnhem (verlauf) and en:Amsterdam–Arnhem railway (route map). The first problem is that the language wikis dont use the same symbol set, so it is imposible to copy and paste from one langauge to an other. This causes a lot of duplicate work. It would be more efficient to maintain the information in one place for al the languages. Only descriptions and comments differ by langauge. However placenames can be standardized with Wikidata.
Proposed solution: *First and prerequisite fase: standardise the symbolset so it can be used in all langauges.
Second: Standardize via Wikidata the definitions of the routes. In principle the railway lines should be defined in the main language wiki of the country. For example: Dutch railway lines are defined by NL wiki, the German railway lines by de wiki. Today all wiki's have the freedom to divide up the railway network in line articles as they see fit. There are some conventions: For example read: Commons:Category:Railway lines in Belgium. In the Netherlands this is based on historic lines. example: nl:Spoorlijn Utrecht - Kampen (Kampen - Zwolle in today's rail network is not logicaly connected with Zwolle Utrecht)
Third. make a central repository. I dont know where. It could be in Wikidata connecting all the elements of route, but it may be to much 'content' for wikidata. Maybe better as special type of file in the Commons. It has to be defined flexibly. It should be posible to use only part of the route. From point A to B. Some wiki's use a simplified version and not the most complete in the repository. Wiki?s should be able te specify that they dont need certain elements (for example all road and river crossing, or eliminate all references to historic lines, junction etc to show the line as it is today)
Who would benefit: Editors of articles, who can copy over the route information from other languages or central repositry in (wikidata?). Updates can then be done centraly.