body .wpex-quantity-btns {
position: static;
top: auto;
right: auto;
width: auto;
border: 0;
}
.woocommerce .quantity .wpex-quantity-btns .plus,
.woocommerce .quantity .wpex-quantity-btns .minus {
position: absolute;
top: 0;
width: 30px;
border: 1px solid #e4e4e4;
height: 100%;
display: flex;
align-items: center;
justify-content: center;
text-decoration: none;
}
.woocommerce .quantity .wpex-quantity-btns .plus {
right: 0;
border-left: 0;
}
.woocommerce .quantity .wpex-quantity-btns .plus::after {
display: none;
}
.woocommerce .quantity .wpex-quantity-btns .minus {
left: 0;
border-right: 0;
}
.woocommerce .quantity {
position: relative;
padding-left: 30px;
padding-right: 30px;
}
.woocommerce .quantity.buttons_added input[type=number] {
margin-right: 0;
margin-left: 0;
}
Snippets: Left/Right WooCommerce Quantity Selector Arrows
Result:

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