I haven't used them since Brexit, but I have ordered from the German, French and Spanish sites a few times. For any expensive items it's well worth heading along to the likes of https://www.hagglezon.com/ and see which site is cheapest, in some cases the savings can be fairly chunky.
Just by way of comparison I ordered stuff from a uk website the other day and safe to say I won’t be doing it again if it can be avoided.
I ordered something from Amazon UK recently. It came to €25.36 (£21. 91) including Irish VAT but free postage. It arrived fairly promptly with no extra charges.For VAT purposes the value is the (cost plus handling, transport and insurance, plus any customs duty). Its this "value" that needs to be under the €22 limit, not the cost of the goods only. Irish VAT is calculated on the value. (No UK VAT should be charged)