Is there any Userscript that enables me to add people to a trust list and then view the trust based on that list and not mine, or according to another user's list?
I haven't seen such a userscript, and I doubt anyone would use it if it instantly overwrites your own Trust list.
The format doesn't make it easy to copy someone else's complete Trust list. This is intentional.
As for the reason for asking, is because trust list for some board, for example, Collectibles board members gives more accurate results than default trust list or my customized trust because they deal with these members, and therefore their feedbacks in that board should be more useful even if they are not DT1/2 members.
I thing many users of the Collectibles board use the Trust system
incorrectly. They leave feedback and include people based on transactions that didn't involve any risk and couldn't have resulted in them getting scammed.
But by all means, if you thing someone leaves good feedback, just include them on your Trust list. You may want to read my
Beginners guide to correct use of the Trust system before doing so.