Here's a road sign.

I got the idea from a danekbel's fantastic plugin (destination sign).

Although it is late, updated it. Please delete the existing folder completely.

updated...

1. Touch to reverse
2. Four-way automatic switching (when installed on a one-way road)
3. Add a two-way sign
4. diagonal road support

There is already a better plug-in created by @rjroldan1 I found out later.

Next time, I will search carefully and make a plug-in. The address is as follows :

https://theotown.com/forum/viewtopic.php?f=63&t=4183