I want to have my Stack Exchange flair on all stack exchange websites. Is that possible? Can it be implemented?
Considered off-topic as personal and not appropriate - also yes.
As the help center states:
Do not use signature, taglines, or greetings.
Every post you make is already “signed” with your standard user card, which links directly back to your user page. If you use an additional signature or tagline, it will be removed to reduce noise in the questions and answers.
However, on your profile, if you include (by copying and pasting):
<a href="https://stackexchange.com/users/15514439/haversine"><img src="https://stackexchange.com/users/flair/15514439.png" width="208" height="58" alt="profile for Haversine on Stack Exchange, a network of free, community-driven Q&A sites" title="profile for Haversine on Stack Exchange, a network of free, community-driven Q&A sites" /></a>
You get this:
You will find the code here.
Paste it into your profile on a site say meta here. You'll get the option to copy it onto all site's profiles.
As the help center sais:
Your user page belongs to you — fill it with information about your interests, links to stuff you’ve worked on, or whatever else you like!