In Java Edition, trial chambers supply chest has chance of giving 4-8 arrows of slowness. In Bedrock Edition, it has chance of giving 4-8 arrows of swiftness instead of arrows of slowness, which doesn't match Java Edition.

Steps to Reproduce:

1. Run /loot give @a loot "chests/trial_chambers/supply" command several times
2. Observe the items given by commands

Observed Results:
They give arrows of swiftness.

Expected Results:
They should give arrows of slowness just like Java Edition.

Code Analysis:
The loot table from /behavior_packs/vanilla_1.21.0/loot_tables/chests/trial_chambers/supply.json in Bedrock Edition:

        {
          "type": "item",
          "name": "minecraft:arrow",
          "weight": 1,
          "aux_val": 17,
          "functions": [
            {
              "function": "set_count",
              "count": {
                "min": 4,
                "max": 8
              }
            },
            {
              "function": "set_data",
              "data": 17
            }
          ]
        }

Can find that the aux value of arrow is 17, which means that loot table will give arrows of swiftness.

The loot table from data/minecraft/loot_tables/chests/trial_chambers/supply.json in Java Edition:

        {
          "type": "minecraft:item",
          "functions": [
            {
              "add": false,
              "count": {
                "type": "minecraft:uniform",
                "max": 8.0,
                "min": 4.0
              },
              "function": "minecraft:set_count"
            },
            {
              "function": "minecraft:set_potion",
              "id": "minecraft:slowness"
            }
          ],
          "name": "minecraft:tipped_arrow"
        }

How to Fix:
Changing the aux value of arrow from 17 (mean swiftness) to 18 (mean slowness) will resolve this issue.