I added few Lua scripts to be able to use normally in free battle.

ccFreeBattleIa_RestoreFreeBattleCamera

• This Lua script restore camera functionality in free battle.

ccFreeBattleIa_AllDispOff

• This Lua script hide all characters on scene.

ccFreeBattleIa_AllDispOn

• This Lua script unhide all characters on scene.

ccFreeBattleIa_BackgroundDrawOff

• This Lua script hide stage on scene.

ccFreeBattleIa_BackgroundDrawOn

• This Lua script unhide stage on scene.

ccFreeBattleIa_HudOn

• This Lua script hide HUD on scene.

ccFreeBattleIa_HudOf

• This Lua script unhide HUD on scene.

How to call scripts in IA Scene.

I created functions inside of game scripts so you could call them, this is how they look like, pretty much simple.

function IA_FB_RestoreFreeBattleCamera( frame, timing )

	if( frame == ccIa_transform30Fps( timing ) ) then

		ccFreeBattleIa_RestoreFreeBattleCamera()

	end

end

function IA_FB_AllCharactersDisplayOff( frame, timing )

	if( frame == ccIa_transform30Fps( timing ) ) then

		ccFreeBattleIa_AllDispOff()

	end

end

function IA_FB_AllCharactersDisplayOn( frame, timing )

	if( frame == ccIa_transform30Fps( timing ) ) then

		ccFreeBattleIa_AllDispOn()

	end

end

function IA_FB_BackgroundDrawOff( frame, timing )

	if( frame == ccIa_transform30Fps( timing ) ) then

		ccFreeBattleIa_BackgroundDrawOff()

	end

end

function IA_FB_BackgroundDrawOn( frame, timing )

	if( frame == ccIa_transform30Fps( timing ) ) then

		ccFreeBattleIa_BackgroundDrawOn()

	end

end


function IA_FB_HudOn( frame, timing )

	if( frame == ccIa_transform30Fps( timing ) ) then

		ccFreeBattleIa_HudOn()

	end

end


function IA_FB_HudOff( frame, timing )

	if( frame == ccIa_transform30Fps( timing ) ) then

		ccFreeBattleIa_HudOff()

	end

end

Inside of IA Scene scripts you must to call them like that

  x------------------------------------------------------------------
-- \author L0407-KUBOTA
-- \date   2023/04/04 16:31:50
------------------------------------------------------------------
function IA_SceneMain() local frame = ccIa_GetFrameCount();
-- コマンド
-- アニメーション
IA_createAnimation(frame,0,0,"data/ia/na_0600/na_0600_020.xfbin","d09_4010");

-- イベント
IA_enableDrawStage( frame, 0 );
IA_setCaption( frame, 36, 94, "TheTale_BT_009990" );




IA_FB_RestoreFreeBattleCamera( frame, 0 );
IA_FB_AllCharactersDisplayOff( frame, 0 );
IA_FB_AllCharactersDisplayOn( frame, 0 );
IA_FB_BackgroundDrawOff( frame, 0 );
IA_FB_BackgroundDrawOn( frame, 0 );
IA_FB_HudOn( frame, 0 );
IA_FB_HudOff( frame, 0 );
end;
------------------------------------------------------------------
-- EOF
------------------------------------------------------------------

frame value is current frame of scene. You don't need to change it, but 0 is value when function must be played, change it on whatever you need.

[!NOTE] Note that, IA_FB_RestoreFreeBattleCamera must be played on last frame, cuz it requires restore camera with delay, so game could finish IA scene before restoring camera for free battle, that's important!