How to use Dnlib to Import a runtime types and method from a specific dotnet framework like 4.8

Question

My project is using .NET core "7.0" and the targeted module is "4.8" and when I try to import "GetString" method and inject it to the module using Dnlib, it references the higher version "7.0" instead of "4.8" and the output exe will crash because it can't find that higher reference dll.

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body.Instructions.Add(new Instruction(OpCodes.Call, module.Import(typeof(Encoding).GetMethod("get_UTF8", new Type[] { }))));
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body.Instructions.Add(new Instruction(OpCodes.Callvirt, module.Import(typeof(System.Text.Encoding).GetMethod("GetString", new Type[] { typeof(byte[]), typeof(Int32), typeof(Int32) }))));

Higher version

Any Idea how to import the right version.