@Mutahhar That certainly complicates things, but the process would relatively be the same if you're not using INFILE.

The ArrayHelpers::chunkFile() method, as currently written, wouldn't help since it only works with one table in mind. But it could be modified to use multiple parsers and yield an array of key/value pairs. For example:

$parsers = [
    'model-one' => function($row) { /* code for parse for one model/table */ },
    'model-two' => function($row) { /* code to parse for another model/table */},
];

foreach (ArrayHelpers::chunkFile($smallPath, $parsers, 1000) as $chunk) {
    ModelOne::Insert($chunk['model-one']);
    ModelTwo::Insert($chunk['model-two']);
}

LOAD DATA INFILE is specifically designed to load data into a single table. However, you could load data into a temp table and then run INSERT SELECT statements to insert into the desired tables.

How to Bulk Insert Data