https://steamcommunity.com/id/bmworkshop/myworkshopfiles/?appid=440
Well, it’s awesome and all, but seems that it doesn’t have as many items as it could of have 
Well, actually I had an idea about Half Life themed TF2 weapons a LONG time ago, even before the workshop, but I can’t rally make those myself 
So I’ll just share some of them and hope that maybe somebody from BM workshop picks them up :
- " Scientist’s assistant" - a spas 12 shotgun for engineer - Stats: -15% firing rate; +10% more accurate; +Alt-Fire - Fire both barrels for some metal cost and decreased rate of fire
- " Browning’s medicine" - M2 .50 cal machine gun for heavy - Stats : -20% firing rate; -15% movement speed while deployed; -every bullet unit shoots 2 bullet instead of 4; *60% accuracy (neutral point because it reduces weapons effectiveness in close quarters) . +20% damage *damage ramp-up and fall-off is reduced; + no spin-up noise
- “Crossed Assassin” - black mesa crossbow for sniper : + silent and produces no kill message ( optionally cloacks the body after a Headshot kill ); + 30% faster charge time; +20% damage on headshots; - projectiles aren’t hitscan and have travel time according to the charge; - requires reload after every 5 shots ( basically has a magazine of 5 bolts); -does no damage to buildings ( - 10 ammo optionally)
- " HECU PDA" - replaces engineer’s turret with 2 buildable HECU turrets. Stats: +10% faster build time * health and fire rate are exactly the half normal LVL 2 turret. *requires 150 metal. * while scanning the area uses a visible laser beam of teams collour to aim, but aims a little faster. - can’t be upgraded or ( maybe) resupplied.
- " Snake’s Hand Cannon " - colt python for spy ( i know there is one already, but this is more similar to half-life one, having nickel plating and all
) : +10% damage. - 25% fire rate ( to match the same rate as in Black mesa one), -20% reload speed; +30% damage on headshots. - " Stalker’s stinger" - black mesa rocket launcher for the soldier : - 3 clip capacity; + a laser guidance for the rocke t * can’t be reloaded while the rocket is in the air. + rocket can be detonated midair; + 15% rocket flying speed; + 30% damage on direct hits.
- " Lazy Trapper" - a sticky bomb launcher for the demo which launches trip mines - * launched tripmines emit laser beams; tripmines detonate when the beam is crossed. - can only deploy 5 tripmines; *Alt fire detonates all tripmines set, but detonation is delayed a little and there is some noise indication. +20% damage and blast radius; - tripmines travel 40% less the distance of ordinary stikies
- " Ghost Frier" - a gluon gun for pyro - +100% range. - 75% afterburn damage; +15% direct damage; * disintegrates killed enemies similarly to Cow mangler; * alt fire creates a small field for 35 ammo which destroys all projectiles; +30% damage to buildings.
Feel free to discuss and write down your own ideas