This is definitely not the best way to do this, but I modified the Powerpack Testimonial Slider to be a generic slider using js and css. I wouldn't recommend doing this haha

pp-generic-slider.css

/*Turn Testimonials Module into Generic Slider*/
.fl-builder-pp-testimonials-settings h1,
.fl-builder-pp-testimonials-settings .fl-builder-settings-tabs a:nth-child(2),
.fl-builder-pp-testimonials-settings .fl-builder-settings-tabs a:nth-child(3),
.fl-builder-pp-testimonials-settings #fl-builder-settings-section-heading_fonts,
.fl-builder-pp-testimonials-settings #fl-builder-settings-section-subtitle_fonts{
    display: none;
}
.slider-module.fl-builder-pp-testimonials-settings h1{
    display: block;
}
.slider-module.fl-builder-pp-testimonials-settings .fl-builder-settings-tabs a:nth-child(2){
    display: flex;
}
.fl-builder-pp-testimonials-settings h1::before,
.fl-builder-pp-testimonials-settings #fl-field-heading,
.fl-builder-pp-testimonials-settings #fl-builder-settings-section-image_box,
[data-type="pp_testimonials_form"] #fl-field-subtitle,
[data-type="pp_testimonials_form"] #fl-field-photo{
    display: none !important;
}

pp-generic-slider.js

jQuery(document).ready(function ($) {
    
    if (typeof window.FLBuilderConfig !== 'undefined') {
        // Turn Testimonials Module into Generic Slider
        FLBuilder.addHook('settings-form-init', function() {
            if ($('form.fl-builder-settings').hasClass('fl-builder-pp-testimonials-settings')) {
                $('.fl-lightbox-header h1').text('Slider');
                $('form.fl-builder-pp-testimonials-settings').addClass('slider-module');
                $('.fl-builder-settings-tabs a:nth-child(2)').text('Content');
                $('#fl-builder-settings-section-title_fonts > .fl-builder-settings-section-header > button.fl-builder-settings-title').text('Heading');
                $('#fl-builder-settings-tab-layouts input[name="testimonial_layout"]').val('5');
                $('form.fl-builder-pp-testimonials-settings').find('label:contains("Testimonial"), a:contains("Testimonial")').each(function() {
                    $(this).html($(this).html().replace(/Testimonial/g, 'Slide'));
                });
                $('#fl-builder-blocks-content-modules---powerpack [data-type="pp-testimonials"] .fl-builder-block-title').text('Slider');
    
                // Mutation observer to handle dynamically added new "Slide"
                const observerFormChanges = new MutationObserver(mutations => {
                    mutations.forEach(mutation => {
                        if (mutation.type === 'childList') {
                            $('form.fl-builder-pp-testimonials-settings').find('label:contains("Testimonial"), a:contains("Testimonial")').each(function() {
                                $(this).html($(this).html().replace(/Testimonial/g, 'Slide'));
                            });
                        }
                    });
                });
                
                const configFormChanges = { childList: true, subtree: true };
                const targetNodeFormChanges = document.querySelector('form.fl-builder-pp-testimonials-settings .fl-form-table');
                if (targetNodeFormChanges) {
                    observerFormChanges.observe(targetNodeFormChanges, configFormChanges);
                }
            }
            $('form.fl-builder-settings[data-type="pp_testimonials_form"]').find('#fl-field-title .fl-field-label label').text('Heading');
        });
        $('button[data-view="powerpackmodules"]').on('click', function() {
            setTimeout(function() {
                // Change the module title to 'Slider'
                $('#fl-builder-blocks-content-modules---powerpack [data-type="pp-testimonials"] .fl-builder-block-title').text('Slider');
                
                // Replace the module icon with new SVG
                $('#fl-builder-blocks-content-modules---powerpack [data-type="pp-testimonials"] .fl-builder-block-icon').html('<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 20 20"><rect x="0" fill="none" width="20" height="20"></rect><g><path d="M5 14V6h10v8H5zm-3-1V7h2v6H2zm4-6v6h8V7H6zm10 0h2v6h-2V7zm-3 2V8H7v1h6zm0 3v-2H7v2h6z"></path></g></svg>');
            }, 150); // Adjust timeout as needed
        });

    }
});