how can I get onslaught / frenzy & endurance charges without kills

[['w']]

? any tips ?

[Rikkore]

onslaught - silver flask and a some unqiues
frenzy - some uniques
endurance - enduring cry, jugg, some unqiues

[Zelph]

The frenzy gem can get you frenzy charges.

Onslaught and frenzy charges can be gotten from raider ascendency as well.

[+|A.O|+]

There's a passive called "Swagger", it is for dual wielders.

It gives 10% chance to gain endurance and/or frenzy charge on block.. You can get both on 1 block if the chances roll good.

[['w']]

thx for the input

[Loco]

Doedre's elixir will get you 1 of each charge, but it costs 20% of ES and 10% of life as damage on use.

https://pathofexile.gamepedia.com/Doedre%27s_Elixir

[Baron01]

You can also get veiled enchants from Jun to increase minimum number of charges. These charges can not be consumed by skills such as Immortal Call or Flicker Strike but they still provide their passive benefit to damage, critical hits or damage mitigation.