Just let me say that having all the menus and all the item/monster/weapon/skill names in Japanese is as rough as I've feared.
The language barrier extends into all the little things; doesn't really help if you'd played hundreds or thousands of hours worth of Monster Hunter games before. I can rely on muscle memory for getting to the equipment selection screen and change gear, but there's stuff like the food selection menu (for the felyne skills) or simply not knowing what item exactly I'm supposed to gather on a gathering quest. Sure, you can look all of this up or google translate via smartphone. Still: Ugh.
Stick with it, if you can. You'll get more and more used to things. I have a few translation lists I use for myself for Felyne Kitchen, Skills I am looking for on charms, etc. I actually created a multi-sheet excel page with skills... listed out in order of number of characters =P It felt like work, but it has helped a ton. I just use Evernote but you could have them anywhere that is handy.
Some of my more used kitchen meals for example. Once you recognize the last few characters you'll get used to which combos offer them. It gets easier the more you stay at it!
ネコの報酬金保険 - extra cart
ネコの 秘境探索術 - Felyne Explorer
ネコの おまけ術 - No food loss on death
ネコの 弱いの来い!- weak monster
招きネコの激運 - super lucky cat
ネコの 短期催眠術 - ATK/DEF Boost for 10min
Some skills I personally prioritized finding on charms:
Handicraft 匠
Expert 達人
Attack 攻撃
Tenderizer 痛撃
Charmer 護石王
Perception 観察眼
Critical Boost 会心強化
Evasion 回避性能
Evade Dist 回避距離
CritElemnt 属性会心
Bomb Boost 爆弾強化
Of course as countless others have mentioned, the Google Translate app can be a lifesaver too. For actual parts I may not be able to figure out on my own, I will usually manually scan in the app, then click the blue -> arrow next to the translation screen, copy the characters there and then just head to Kiranico's full item list (which now has dual japanese/english displayed on one page -
https://mhxxx.kiranico.com/item) and do a 'Find in Page' search. Done. With the dual language list it is awesome, as you can see immediately what it is you're looking for.
Yep. It's a silly amount of 'work' just to be able to play. It's worth it to me by a longshot though. After a few times, it is just second nature. I love the series though, and want to play them all. Obviously needing to do this kind of 'work' isn't remotely worth it for others.