Would be amazing if the addon was compatible with classic, most seem to work actually just throwing some lua error i suposed are link to api funct not available in classic.

Message: Interface\AddOns\Bagnon_RequiredLevel\main.lua:209: attempt to call upvalue 'GetProfessions' (a nil value)
Time: Wed Sep 30 23:45:04 2020
Count: 1
Stack: Interface\AddOns\Bagnon_RequiredLevel\main.lua:209: attempt to call upvalue 'GetProfessions' (a nil value)
...erface\AddOns\Bagnon\common\Wildpants\api\events.lua:77: in function ?' ...Ons\Ace3\CallbackHandler-1.0\CallbackHandler-1.0.lua:119: in function <...Ons\Ace3\CallbackHandler-1.0\CallbackHandler-1.0.lua:119> [C]: ? ...Ons\Ace3\CallbackHandler-1.0\CallbackHandler-1.0.lua:29: in function <...Ons\Ace3\CallbackHandler-1.0\CallbackHandler-1.0.lua:25> ...Ons\Ace3\CallbackHandler-1.0\CallbackHandler-1.0.lua:64: in function Fire'
Interface\AddOns\Ace3\AceEvent-3.0\AceEvent-3.0.lua:120: in function <Interface\AddOns\Ace3\AceEvent-3.0\AceEvent-3.0.lua:119>

Locals: self =

{
SendSignal = defined @interface\AddOns\Bagnon\common\Wildpants\libs\WildAddon-1.0\WildAddon-1.0.lua:82
UpdateBags = defined @interface\AddOns\Bagnon\common\Wildpants\api\events.lua:69
RegisterMessage = defined @interface\AddOns\Ace3\CallbackHandler-1.0\CallbackHandler-1.0.lua:90
UnregisterMessage = defined @interface\AddOns\Ace3\CallbackHandler-1.0\CallbackHandler-1.0.lua:153
REAGENTBANK_PURCHASED = defined @interface\AddOns\Bagnon\common\Wildpants\api\events.lua:50
sizes = {
}
firstVisit = true
PLAYERREAGENTBANKSLOTS_CHANGED = defined @interface\AddOns\Bagnon\common\Wildpants\api\events.lua:46
SendMessage = defined @interface\AddOns\Ace3\CallbackHandler-1.0\CallbackHandler-1.0.lua:59
UpdateBankBags = defined @interface\AddOns\Bagnon\common\Wildpants\api\events.lua:81
types = {
}
UnregisterSignal = defined @interface\AddOns\Bagnon\common\Wildpants\libs\WildAddon-1.0\WildAddon-1.0.lua:78
UpdateContent = defined @interface\AddOns\Bagnon\common\Wildpants\api\events.lua:113
CACHE_BANK_OPENED = defined @interface\AddOns\Bagnon\common\Wildpants\api\events.lua:54
UpdateSize = defined @interface\AddOns\Bagnon\common\Wildpants\api\events.lua:89
RegisterEvent = defined @interface\AddOns\Ace3\CallbackHandler-1.0\CallbackHandler-1.0.lua:90
UnregisterAllMessages = defined @interface\AddOns\Ace3\CallbackHandler-1.0\CallbackHandler-1.0.lua:174
UpdateType = defined @interface\AddOns\Bagnon\common\Wildpants\api\events.lua:103
queue = {
}
UnregisterAllEvents = defined @interface\AddOns\Ace3\CallbackHandler-1.0\CallbackHandler-1.0.lua:174
OnEnable = defined @interface\AddOns\Bagnon\common\Wildpants\api\events.lua:20
BAG_UPDATE = defined @interface\AddOns\Bagnon\common\Wildpants\api\events.lua:37
RegisterSignal = defined @interface\AddOns\Bagnon\common\Wildpants\libs\WildAddon-1.0\WildAddon-1.0.lua:74
NewModule = defined @interface\AddOns\Bagnon\common\Wildpants\libs\WildAddon-1.0\WildAddon-1.0.lua:68
PLAYERBANKSLOTS_CHANGED = defined @interface\AddOns\Bagnon\common\Wildpants\api\events.lua:41
UnregisterEvent = defined @interface\AddOns\Ace3\CallbackHandler-1.0\CallbackHandler-1.0.lua:153
Tag = "BAGNON_"
}
(for generator) = defined =[C]:-1
(for state) = {
-2 = true
}
(for control) = 0
bag = 0

That's a bug report from Bagnon RequiredLevel, a completely different addon.

Anyway, the bagnon versions in classic and retail are completely different, based on completely different code. It's not a matter of changing a few API calls, it's a matter of writing a completely new addon. I'm not even certain bagnon for classic accepts plugins, at least not in the same easy manner.

I have no plans of writing any plugins for bagnon for classic. Sorry!