Hi, I have very similar hyperpigmentation on my cheeks and forehead.
To prevent more sun damage I use full spectrum factor 50 sunscreen every day, all year round. I use one that is creamy so this is my daily face cream. I use it every day even if not going outside. I am generally thrifty but I happily spend big on a really good one, as this is the most important part of my skincare routine.
In use retinol , but it’s not for everyone and if you have v sensitive skin I would start with a very gentle one and mix it with your night face cream to start with. I use the inkey list retinol cream.
another option is tranexemic acid… it’s not an acid that resurfaces, so not strong or burney. This is a long term thing rather than quicker fix.
there’s also alpha arbutin… similar to above.Superdrug do an own brand serum and it can be used morning/night before face cream.
some people like niacinamide for hyperpigmentation, it doesn’t work well for my skin so I don’t use it.
check out the inkey list and the ordinary. They are both Buget friendly brands that focus on single ingredient skincare, good quality and straightforward in my opinion.
there are usually little questionnaires etc that you can do on websites for skincare brands, where you put in your main concerns (hyperpigmentation and sensitive skin? ) and they suggest products.
my advice is don’t try loads at once.
use good quality sunscreen daily and add in one product to address the hyperpigmentation- it will likely take a few months to see the difference.
you are correct that the HRT could have kickstarted the hyperpigmentation, this is generally considered to be melasma if it’s hormone related. In pregnancy many women get this, it’s nicknamed ‘the mask of pregnancy’ .
I’ve learned to (try) and embrace or just accept my hyperpigmentation. I take steps to minimise it , but it comes out strong in the summer despite me wearing sunscreen, avoiding sun in my face, wearing hats etc.
if I want to try and cover it I use a peachy coloured colour corrector under concealer or foundation. With just foundation/concealer it shows though as a grey colour… but with peach / pink colour corrector it balances the brown before concealing. I use huda colour corrector- I think the shade is cherry blossom- it’s more pink than salmon, which works for me as I’m pale too. I do have the peach/salmon colour one too, and sometimes mix them if I feel I need more peach tone to correct really dark bits.