I don't think that strike exists as ascii code, and I don't think it could be supported by IRC servers.
AFAIK, you can only use:
\003 => colors
\002 => bold
\037 => underline
\026 => italic / inverted (not supported by all ircds)
Strikethrough letters for ASSCI are supported. I've already tested on the Dalnet network, and I've also tested on the ChatZona network and it supports it.
If there is a crossed-out ASCII code for IRC and I have tested it on the dalnet and chatzona networks to see if they support it.
.:an ideal world:. www.geocities.ws/chateo/yo.htm
my programming place /server ix.scay.net:7005
networks: DALnet #tcls ChatZona #tcl Libera.Chat #tcls
CrazyCat Thank you very much, it worked perfectly for me, I already tried it, thanks again
then it would look like this (ASCII).. as long as the IRCD supports it :
\003 => colors
\002 => bold
\037 => underline
\026 => italic / inverted (not supported by all ircds)
\036 => Strikethrough
.:an ideal world:. www.geocities.ws/chateo/yo.htm
my programming place /server ix.scay.net:7005
networks: DALnet #tcls ChatZona #tcl Libera.Chat #tcls
Little precision: ircd's doesn't care of control codes, they send them to client (or sometime filter them, but rarely).
So, the render is only depending on client.
Flashcode had added the strikethrougt interpretation in weechat today, but as it uses ncurses and ncurses doesn't manage strikethrought, we (I proposed, Flashcode choose) choose to use "half bright" rendering.