此方法高效实用，避免了不同平台下载两份GTA5多占用空间，也解决了硬链接方法产生的STEAM每次登录验证完整性的问题。
如果本地Steam已安装GTAV，但Epic未安装。那么不需要重新安装即可在Epic上畅玩。EPIC与STEAM游戏文件共享（GTAV）的方法如下：
1.先寻找STEAM已安装的GTAV的文件路径，并确定EPIC上GTAV的安装路径，如：
D:\Application\Steam\steamapps\common\Grand Theft Auto V
D:\Application\Epic Games\GTAV
2.EPIC点击下载，刚开始下载后任务管理器终结EPIC进程。
3.以管理员身份cmd运行：
mklink /J "D:\Application\Epic Games\GTAV\update" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\update"
mklink /J "D:\Application\Epic Games\GTAV\x64" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64"
mklink /h "D:\Application\Epic Games\GTAV\x64a.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64a.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64b.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64b.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64c.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64c.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64d.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64d.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64e.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64e.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64f.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64f.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64g.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64g.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64h.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64h.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64i.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64i.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64j.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64j.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64k.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64k.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64l.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64l.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64m.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64m.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64n.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64n.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64o.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64o.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64p.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64p.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64q.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64q.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64r.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64r.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64s.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64s.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64t.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64t.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64u.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64u.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64v.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64v.rpf"
mklink /h "D:\Application\Epic Games\GTAV\x64w.rpf" "D:\Application\Steam\steamapps\common\Grand Theft Auto V\x64w.rpf"4.打开Epic，验证完整性，完成。
Q：为什么不直接创建从 D:\Application\Epic Games\GTAV 到 D:\Application\Steam\steamapps\common\Grand Theft Auto V 的链接，而是“麻烦”的创建这么多主要文件的链接呢？
A：因为Epic和Steam的激活认证文件是不同的。如果直接将Steam的GTAV原封不动链接过来，Epic下次启动必须重新检查完整性，并且会自行替换不正确的激活文件，而且在Epic上成功打开GTAV以后，下次在STEAM上运行又会检查完整性，并替换成Steam自己的激活文件。这样反复检查完整性，并不是我们的初衷——想在Steam上打开就在Steam上打开，想在Epic上打开就在Epic上打开。