Board Thread:General Discussion/@comment-28047728-20160324184120/@comment-1038387-20160324185319

It's not really "Crossovers", more like "guest appearances".

Flashpoint is an alternate universe. Non-canon. I think he only appears in issues #1 and #2 of the Deathstroke and the Curse of the Ravager series.

I haven't read every Convergence tie-in issue, but I think it's just issues #4 and #5 of the main series.