Convert ScopeQuery to SearchStringModels using Sitecore PowerShell Extensions.

ScopeQueryToSearchStringModels.ps1

#$provider = [Sitecore.DependencyInjection.ServiceLocator]::ServiceProvider.GetService([Sitecore.XA.Foundation.Abstractions.Configuration.IConfiguration[Sitecore.XA.Foundation.Search.SearchConfiguration]]).GetConfiguration().QueryMaxItems

$query = "+template:{51ed5851-1a61-4dae-b803-6c7fae6b43d8};+sxa:SameFirstTagAsCurrentPage|SxaTags;custom:EventStartDate|[NOW TO *];custom:EventEndDate|[NOW TO *];sort:eventstartdate;sort:isfeatured[desc]"
$modelList = [Sitecore.ContentSearch.Utilities.SearchStringModel]::ParseDatasourceString($query)
$contextItem = Get-Item -Path "master:" -ID "{31318AEE-310B-4EE4-84DA-4B84471E0FCA}"
[Sitecore.DependencyInjection.ServiceLocator]::ServiceProvider.GetService([Sitecore.XA.Foundation.Search.Services.ISearchQueryTokenResolver]).Resolve($modelList, $contextItem)

class CustomSearchResultItem : SearchResultItem
{
   [Sitecore.ContentSearch.IndexField("eventstartdate_tdt")]
   [DateTime]$EventStartDate
   
   [Sitecore.ContentSearch.IndexField("isfeatured_b")]
   [bool]$IsFeatured
}

$props = @{
    Index = "sitecore_sxa_concentra_master_index"
    QueryType = [CustomSearchResultItem]
    ScopeQuery = "+template:{51ed5851-1a61-4dae-b803-6c7fae6b43d8};+custom:sxatags|Operations;+custom:sxatags|Accounting and Finance;custom:EventStartDate|[NOW TO *];custom:EventEndDate|[NOW TO *];sort:eventstartdate;sort:isfeatured[desc]"
}
Find-Item @props

SimpleSearchResultItem.cs

using System.ComponentModel;
using Sitecore.ContentSearch;
using Sitecore.ContentSearch.Converters;
using Sitecore.ContentSearch.SearchTypes;
using Sitecore.Data;

namespace Spe.Commands.Data.Search
{
    public class SimpleSearchResultItem : ISearchResult
    {
        public string this[string index] { get => null; set => _ = value; }
        public object this[ObjectIndexerKey key] { get => null; set => _ = value; }

        [IndexField("_group")] 
        [TypeConverter(typeof(IndexFieldIDValueConverter))] 
        public virtual ID ItemId { get; set; }   

        [IndexField("_name")] 
        public virtual string Name { get; set; }

        [IndexField("_content")]
        public virtual string  Content { get; set; }

        [IndexField("_datasource")]
        public virtual string Datasource { get; set; }
    }
}