Where to farm sanguine weapon recipes?

[swightly]

Other than schematics rng and the treasure hunter vendor

[Glyph]

You've named both the ways you'd likely farm tier 3 books. If you have an excess of greater stygian shards somehow you can summon a blood witch at the summoning circle for guaranteed book drops.

[V I R A L]

Bosses , find a act 4/5 boss that you can kill it easily as much as you can. They usually drop 1 book in 2-4 runs ( ofc not guarantee sanguine everytime but still better than waiting for random drop ), even 2 if you are lucky.
I usually farm Terrorclaw and Voltatia for books , then Styx later for weapon shards and tier 4 jewels .

[Akulvo]

Any of the t4 bosses that are easy for you to kill quickly I guess

Though honestly, just going on killing sprees in the capital for scrolls and schematics is good, especially since you also get gold in the process. Turn all your scrolls into schematics and then use the gold to buy ♥♥♥♥ from the treasure collector and you're set.

At least, thats how I grind for schematics. The scroll grind honestly takes a lot longer for t2 research than the t3.