Flurl doest not format query params based on newtonsoft json namin strategy like body content does, so I created a base class for translate it.

public abstract class FlurlBaseQueryParam
{
    public Dictionary<string, string> ParseQueryParams()
    {
        var stringParams = JsonConvert.SerializeObject(this, settings: new JsonSerializerSettings()
        {
            NullValueHandling = NullValueHandling.Ignore
        });
        return JsonConvert.DeserializeObject<Dictionary<string, string>>(stringParams, new KeyValuePairConverter());
    }
}

Then you can inherit and apply the naming strategy for each object as follows in the example below.

• CamelCaseNamingStrategy
• SnakeCaseNamingStrategy
• KebabCaseNamingStrategy

[JsonObject(NamingStrategyType = typeof(CamelCaseNamingStrategy))]
public class GetByParamRequest : FlurlBaseQueryParam
{
    public string Identification { get; set; }
    public string Email { get; set; }
}

And then you should call the ParseQueryParams method inside the SetQueryParams method, as follows.

public async Task<ResponseModel> GetByParamAsync(GetByParamRequest request)
{
    try
    {
        return await Url.SetQueryParams(request.ParseQueryParams())
            .GetJsonAsync<ResponseModel>();
    }
    catch (FlurlHttpException e)
    {
    }

    return new ResponseModel();
}