This trips up more players than almost anything else in the game, so let's actually walk through it properly.
The default behavior most people don't expect
In vanilla Rust, blueprint research is entirely personal. If you research a rifle at a workbench, only your character knows how to craft it — your teammate standing right next to you, even on the same official in-game team, does not automatically learn it too. Each player has to individually spend the scrap and research the item themselves, or receive the actual blueprint item and learn it manually.
This catches new players out constantly, because the in-game Team system implies a lot of shared context (map markers, shared vision, coordinated pings) and blueprints just... aren't part of that. It's a completely separate system.
Why this matters more than it sounds like it should
Scrap is one of the most valuable resources in the game, and blueprint research eats a lot of it, especially for mid and late-tier items. If a 3-person team is all individually researching the same weapons and building pieces separately, that's 3x the scrap cost for the exact same functional outcome as if it had just been shared once. On a wipe with any kind of time pressure — which is most wipes — that's a genuinely significant waste.
How servers fix this
Some servers run a plugin that automatically shares blueprints across teammates, clan members, or even a friends list, depending on how it's configured. Once one person researches an item, everyone else in that group instantly knows it too — no manual re-research needed. Good implementations of this also handle edge cases properly: what happens if someone leaves the team mid-wipe (do they keep the blueprints they already learned, or lose access), and whether new members who join partway through the wipe get retroactively caught up on everything the team's already researched.
On our server specifically, we run this with new members getting caught up automatically when they join a team, and members keeping what they've learned even if they leave later — so nobody loses progress just from a team roster changing mid-wipe.
What to check as a player
If you're joining a new server and planning to play as a team, it's worth actually asking (or checking server rules/Discord) whether blueprint sharing is enabled before you commit to a research strategy. If it's not enabled, the practical move is to divide research responsibilities deliberately — have one person specialize in weapons research, another in building/base tech — rather than everyone researching the same things in an uncoordinated scramble and wasting scrap across the whole team.