Use Multiple Google Fonts - benjaminkott/bootstrap_package GitHub Wiki

constants.typoscript

page {
    theme {
        googleFont {
            enable = 0
        }
    }
}
plugin.bootstrap_package.settings.scss {
    font-family-base = 'Oswald', sans-serif
    font-weight-normal = 400
    headings-font-family = 'Amatic SC', cursive
    headings-font-weight = 700
}

setup.typoscript

page {
    includeCSSLibs {
        font = https://fonts.googleapis.com/css?family=Amatic+SC:700|Oswald:400,700&display=swap
        font {
            external = 1
            disableCompression = 1
            excludeFromConcatenation = 1
        }
    }
}